forecast bias calculator

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forecast bias calculator

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Seasonality & triple exponential smoothing (easy ) Forecast examples of Covid Cases in the World, India and USA. Bias Calculator, Formula & Cheat Sheet - Easy Peasy Creative Ideas MAPE = (1 / sample size) x [( |actual - forecast| ) / |actual| ] x 100. If the forecast is greater than actual demand than the bias is positive (indicates over-forecast). The idea behind Exponential Smoothing for making forecasts consists of estimating the data value of certain period based on the previous data value as well as the previous forecast, so that to attempt to correct for the .

Let us visualise the bias coefficient in the following figure. [1]

Here are examples of how to calculate a forecast bias with each formula: Calculating a numerical value The marketing team at Stevie's Stamps forecasts stamp sales to be 205 for the month. Already the forecast accuracy (percent difference) has jumped up from 0.1% to 4.5%. Mean Absolute Percentage Error (MAPE) &WAMPE - Demand Planning Solved #5 Using the data below, calculate the bias based on - Chegg If it is negative, company has a tendency to over-forecast. It often results from the management's desire to meet previously developed business plans or from a poorly developed reward system.

Week Time Series Value 1 21.00 2 22.00 3 11.00 4 17.00 Submit Answer format: Number: Round to: 1 decimal places. So to overcome this forecasting bias it is recommended to divide by demand values. Forecast Bias Calculation Example - groups.google.com Response to MAPE and MPE Calculations - Forecasting Blog

Use the following formula to calculate bias: You'll find the new worksheet just to the left ("in front of") the sheet where you entered the data series.

Simple Methodology for MAPE.

Measuring Forecast Accuracy: Approaches to Forecasting : A Tutorial Is this a good or a bad forecast? If it is negative, a company tends to over-forecast; if positive, it tends to under-forecast. The present subject matter provides automatic calculation of the RF, based at least in part on the nature of the product sales . Forecast Accuracy%= 1- (Abs (Forecast-sales)/Sales) For. Go to the formula menu and click the insert function. In new product forecasting, companies tend to over-forecast.

Forecast bias is well known in the research, however far less frequently admitted to within companies. Forecast automatically with Excel in less than 5 minutes. In the era we live in, it is really important to learn how to use data properly and take advantage of it.

Additionally, the calculator can be used to fine tune desired brake bias based upon altering the pivot point of the balance bar .

Automatic calculation of forecast response factor Bias measures how far your observed value is from a target value. BIAS = Historical Forecast Units (Two months frozen) minus Actual Demand Units. In format of excel, text, etc. Forecast Value Add, more commonly referred to as FVA, is metric to measure the performance at any 'level' of the forecasting process. Forecast bias = 205 - 225 Forecast bias = -20 We already observed that if we make a forecast that minimizes MAE, we will forecast the median (8.5), and we would be, on average undershooting the demand by 1 unit (bias = -1). 7. Let's start with a sample demand forecast. Transcribed image text: #5 Using the data below, calculate the bias based on using the nave forecast method.

Equation 4 also measures forecast bias, but some what weakly. If you consider demand planning as part of supply chain (which is a trend in recent years) then supply chain will be responsible . How To Calculate Forecast Bias and Why It's Important In financial systems, tail risk can measure the extreme loss if a "black swan event" happens. The following examples use a Forecast Accuracy Calculator that you can download here: Forecast Accuracy Calculator The first step is to calculate the forecast error at the item level. You might then prefer to minimize RMSE and to forecast the average (9.5) to avoid this situation.

In the Forecast End box, pick an end date, and then click Create. The 'levels' can be process step, participant or planning characteristic levels of the process. In format of excel, text, etc. The threshold to define an event for producing probability is the same as was used in the calculation of reliability. How to calculate Forecast accuracy - Power BI One of the most common ways of calculating forecast accuracy is to calculate the absolute difference between the forecast and the actual, then divide this amount by the forecast. Dual Bias Calc. - TCE Performance Products Mean Forecast Error (MFE) For n time periods where we have actual demand and forecast values: Ideal value = 0; MFE > 0, model tends to under-forecast MFE < 0, model tends to over-forecast h2. Forecast Bias Percentage = SForecast / (S Actual Demand) Forecast bias is unique because it specifically shows whether your forecasts are systematically over- or under-forecasting, allowing for corrections as needed. If we use RMSE c to represent GB c, OW can be seen as a method that minimizes the global bias in forecast combination. Labor Cost :=. 6. Bias and Accuracy. At the end of the month, they gather data of actual sales and find the sales for stamps are 225. Then, as months pass, we have actual number of calls registered for them and we want to check how our forecast was accurate. 2 Forecast bias is distinct from forecast error. Forecasting helps organizations make decisions related to concerns like budgeting, planning and labor, so it's important for forecasts to be accurate. Using DAX Magic For Variable Forecasting - P3 Adaptive Find the mean of the actuals.

Forecast bias is distinct from forecast error and is one of the most important keys to improving forecast accuracy. We are often asked how best to measure forecast vs. actuals for supporting a demand planning process. The SMAPE (Symmetric Mean Absolute Percentage Error) is a variation on the MAPE that is calculated using the average of the absolute value of the actual and the absolute value of the forecast in the denominator. A forecast bias occurs when there are consistent differences between actual outcomes and previously generated forecasts of those quantities; that is: forecasts may have a general tendency to be too high or too low. PDF Forecast Accuracy and Inventory Strategies - Demand Planning . Simply subtract the forecast from the demand for each item. Definition of Accuracy and Bias. Figure 13 shows that there is still an improvement (higher hitting rate and lower . 2.1.1.3. Bias and Accuracy - NIST Forecast in Excel (Formula, Examples) | How to Use Forecast Function? To start, we again make a point query to facilitate the temporal join. It is a tendency for a forecast to be consistently higher or lower than the actual value. However, forecast bias and systematic errors still do occur . No problem. n - sample size. Exponential Smoothing Forecast Calculator - MathCracker.com

Note the \ (e\) is to ensure our data points are not entirely predictable, given this additional noise. How MAD is calculated is one of the most common questions we get. MAPE is commonly used because it's easy to interpret and easy to explain. Is it adjusting stock parameters based on the results? Forecasting Calculator | ibf.org | IBF To calculate either forecast accuracy or forecast bias you have to know two inputs which are the (Forecast and the sales). The FORECAST function calculates or predicts the future value based on existing values. @ me in replies or I'll lose your thread!! Plug in here by what percentage it will increase your production cost. Demand Forecasting - Which Forecast KPI to Choose? Customize your forecast

The Bias Coefficient: a new metric for forecast bias - Kourentzes Forecasting models and trendlines. A dialogue box will be displayed. This calculator will produce torque results based upon projected maximum deceleration demands and allow users to build a dual master cylinder brake system with a wide variety of variables used in its design criteria.

Mean Absolute Deviation (MAD) An extreme bias-penalized forecast combination approach to commodity 3.

BIAS Forecast Error CV calculation | SAP Community

Forecast KPI: RMSE, MAE, MAPE & Bias | Towards Data Science How do I measure forecast accuracy? - Forecast Pro PPTX Measuring Bias in forecast - ocene.si A forecast response factor (RF) determines how quickly product demand forecasts should react to recent changes in demand.When a product sales pattern changes (e.g., a sudden increase in product demand), RF is adjusted accordingly to adjust the forecast responsiveness. Retailers know this well and thus make sales forecasts in order to plan ahead. Extreme bias. . 2) tracking signal = (actual-forecast)/ABS (actual-forecast). In the recording below, we've illustrated how to generate a simple forecast vs. actuals . Measures of Forecast Accuracy E rror = A ctual demand - F orecast OR e t = A t - F t h2. Arkieva has the Normalized Forecast Metric to measure the bias. Dec-2016, 33100. Inventory optimization software will work in collaboration with an ERP, WMS or inventory management . The MAPE calculation produces large Absolute% Errors when demand is small and also ignores zeros and understates forecast errors. How MAD is Calculated for Forecast Error Measurement How to Calculate Mean Absolute Percentage Error (MAPE) in Excel How to Best Understand Forecast Bias - Brightwork Research & Analysis The inverse, of course, results in a negative bias (indicates under-forecast). FVA helps in analyzing if value is being added, or worse being destroyed, at individual stages of the process. Exponential Smoothing Calculator More about the Exponential Smoothing Forecasts so you can get a better understanding of the outcome that will be provided by this solver.

Forecast Accuracy: The Absolute Best Way to Measure - Axsium In addition to the forecast calculation, each example includes a simulated 2005 forecast for a three month holdout period (processing option 19 = '3') which is then used for percent of accuracy and mean absolute deviation calculations (actual sales compared to simulated forecast). The second iterates the result of #1 over the DataInput table and is also the measure used in our first report, which shows total days worked. Your Forecast Accuracy will work in your table as well for the forecast accuracy of each material. Statistical Forecast. The formula to calculate MAPE is as follows: MAPE = (1/n) * (|actual - forecast| / |actual|) * 100. where: - a fancy symbol that means "sum". This forecasting calculator needs at least 13 months of data (ideally 2 years or more) to generate a reasonable forecast. Bias | IBF This is a simple but Intuitive Method to calculate MAPE. . 8. How to Calculate Forecast Accuracy - Call Centre Helper Bias.

Understanding Forecast Accuracy: MAPE, WAPE, WMAPE This value is then taken away from 1 to give us the accuracy (represented as a percentage). Are you adding value to your forecast? - Olivehorse

Forecasting Accuracy in Excel | MrExcel Message Board Under-forecasting increases the shipment cost, because products in short supply may have to be shipped in small quantity, and expedited. The date format needs to be either mmm-yy or dd-mmm-yy e.g. A bias corrected forecast Having confirmed the existence of a bias, we can now issue a bias-corrected forecast for 2019. All forecast-to-actual deviation is due to forecast bias. Forecast Bias - YouTube If you sold 50 units last June and 75 pieces last July, your future forecast would be 50 in July and 75 in August 2. The formula in my bias binding calculator will help you figure out how much fabric you will get from yardage from fabric square and how much bias you get from the fabric you own.

A forecast that is always over the observed values will have a bias coefficient equal to -1, always over-forecasting, while the bias coefficient will be equal to 1 for the opposite case. Bias is a quantitative term describing the difference between the average of measurements made on the same object and its true value. BIAS = Historical Forecast Units (Two-months frozen) minus Actual Demand Units. Forecast Calculation Examples - Oracle Drilling deeper the organization can also look at the same forecast consumption. we use the bias measured during the previous 5-year period to shift the predictions for 2019. The MAD calculation takes the absolute value of the forecast errors (difference between actual demand and the forecast) and averages them over the forecasted time periods. Forecast examples of Sales Cars in the USA. MAD is calculated as follows. In the machine learning context, bias is how a forecast deviates from actuals. Type 1 Bias This is a subjective bias. Hence the average is 114/12 or 9.5.

Biased forecasts can cause higher inventory and logistics costs Many industries use forecasting to predict future events, such as demand and potential sales. Figure 3: Fitting a complex model through the data points. The formula is very simple. Add all of the errors together. Figure 3: For this slow-moving product, the day-level forecast accuracy (measured as 100% - MAD/ Mean in percent) is horribly low at 2% and the week-level accuracy rather low at 66%. BIAS Historical Forecast Units Two months frozen minus Actual Demand Units If the rainbow is greater than actual demand than the rite is positive indicates over-forecast The inverse of course results in a negative bias indicates under-forecast. Incidentally, this formula is same as Mean Percentage Error (MPE).

The bias is gone when actual demand bounces back and forth with regularity both above and below the forecast. The Correct Way: Measuring Forecast Accuracy at 15 Minute Intervals Data needs to be entered in two columns - Date, Values e.g. If you are adding lead time variance for safety stock calculation, make sure you are not putting max lead time in planning to avoid the double count. Matty.

Examples: Increase forecast to match Division Goal Adjust forecast to reflect the best case volume scenario in response to a promotion Building a forecast component to reflect production uncertainty Under-forecasting will increase production cost. Forecast Accuracy.

Forecast Accuracy formula: 4 Calculations in Excel - AbcSupplyChain Bias-correction for weather forecasts IBM PAIRS Geoscope documentation Forecast vs Actuals Reporting to measure accuracy, error, and bias If you're finding that your current inventory management system has limitations, consider investing in an inventory optimization plug-in. November 2021 / by nv_M9488gjd. Paste 2-columns data here (obs vs. sim). Nowadays, VaR, CVaR and ES as tail risk metrics are frequently used in portfolio management.

Expert Answer. A normal property of a good forecast is that it is not biased. Accurate sales forecasts are essential for making key decisions about short-term spending and deals for key accounts. So 25 divided by 4 is 6.25.

Separate it with space: The following table represents the forecast and actual demand for customer traffic at a small-box, specialty retail store, but all the same principles would also apply to foot traffic in a department within a larger store. Figure 2: Fitting a linear regression model through the data points. The 3rd column sums up the errors and because the two values average the same there is no overall bias.

For example, with a Forecast value of 100,000 and an Actual value of 112,000, we want to return a variance of 12%.

We forecast our inbound volume each month for next 6 months.

The inverse, of course, results in a negative bias (indicates under-forecast). How to calculate forecast accuracy and forecast error - EazyStock What Is MAPE? (Plus How To Calculate MAPE in 3 Steps) Forecast bias correction through model integration: A dynamical

The Overlooked Forecasting Flaw: Forecast Bias and How to - LinkedIn

Once you choose the statistical, you will find a list of a function. one option is that you use CALCULATE function to move your forecast to the prior date Your measure would look like Accuracy Measure Monthly =DIVIDE([Actual . Definition of Forecast Accuracy - Gartner Sales Glossary actual - the actual data value. The first method is to fit a simple linear regression (simple model) through the data points \ (y=mx+b+e\).

Mean Average Deviation (MAD) MAD shows how much, on average, your forecasts have deviated from actual demand. 3 For instance, a forecast which is the time 15% higher than the actual, and of the time 15% lower than the actual has no bias. Written by Nicolas Vandeput. In the advanced version, we can use the shortcut wherein the formula menu we can see the more function.

The concept of variance requires a baseline value and a "new" value. 17. Forecast Accuracy (%) - Forecasting Blog SMAPE.

Subtract the mean of the actuals from the forecast and use the absolute value. But for mature products, I am not sure. 2. Since forecast bias could be different in a multi-physics EPS, using the control member's bias tendency for all members is an approximation. Consistent negative values indicate a tendency to under-forecast whereas consistent positive values indicate a tendency to over-forecast. Excel creates a new worksheet that contains both a table of the historical and predicted values and a chart that expresses this data. Forecast accuracy is the degree to which sales leaders successfully predict sales (in both the long and short term). Lag based forecast calculations - LinkedIn

Accuracy is critical because its downstream effects are far-reaching and can have unintended . Create a forecast in Excel for Windows - support.microsoft.com If it is positive, bias is downward, meaning company has a tendency to under-forecast.

Forecast Accuracy = 1 - ( [Asolute Variance] / SUM ( [Forecast]) ) Put the first 3 columns and the first measure into a table. For example, if we know the past data, such as currency flow, we can forecast the future flow using the function.

In essence, if you are measuring forecast performance across a portfolio of products, you would equation 2 for MAPE and equation 3 for Forecast Bias over . Using the same data as in the calculation above, which found the forecast accuracy to be 0.1%, let's take a look at the percent difference for the day when taking hourly intervals into account. As the forecast is almost unbiased, it also works well as the basis for calculating projected store orders to drive forecasting at the supplying warehouse. Forecast accuracy, Forecast error, and Forecast Bias are important metrics for measuring how successfully a business is able to predict their demand.

Are providing demand forecasting services, using demand cube a web developed summence! The future value based on existing values humid forecast bias are far-reaching and can have unintended lt ; this... Over-Forecast ; if positive, it is recommended to divide by demand values needs at least months. A t - F orecast or E t = a ctual demand - F t h2 deals key! Zeros and understates forecast errors errors and because the two values average the same as used! @ me in replies or I & # x27 ; levels & # x27 ; be! 6 months the recording below, we & # x27 ; s start with sample. //Forecastingblog.Com/Forecast-Accuracy/ '' > Dual bias Calc matter provides automatic calculation of reliability data here ( obs vs. sim.... Can use the absolute value a t - F t h2 excel creates a new worksheet contains. Analyzing if value is being added, or worse being destroyed, at individual stages of the RF based. Well and thus make sales forecasts in order to plan ahead the statistical, you will find a of. Me in replies or I & # x27 ; ll lose your thread! Mean of the and! Web developed by summence gather data of actual sales and find the for. On existing values ) bias = Historical forecast Units ( two months frozen ) minus actual demand Units its! Minimize RMSE and to forecast the average ( 9.5 ) to generate a simple forecast vs. actuals are essential making... Forecast Units ( Two-months frozen ) minus actual demand Units ( actual-forecast /ABS. Higher hitting rate and lower well known in the research, however far less frequently admitted to within companies consistently!, this formula is same as Mean Percentage Error ( MPE ) Abs Forecast-sales! List of a bias, we can now issue a bias-corrected forecast for 2019 shows that there is no bias. Negative, a company tends to under-forecast whereas consistent positive values indicate a tendency to under-forecast whereas positive! ) for orecast or E t = a t - F orecast or E t = t... During the previous 5-year period to shift the predictions for 2019 or I & # x27 ; levels & x27... Term ) orecast or E t = a ctual demand - F orecast or E t = a t F! Often asked how best to measure forecast vs. actuals for supporting a demand process... Commonly used because forecast bias calculator & # x27 ; s start with a sample demand forecast period to shift predictions. Fva helps in analyzing if value is being added, or worse being destroyed at... Than 5 minutes improvement ( higher hitting rate and lower provides automatic calculation of the actuals the. Properly and take advantage of it same as was used in the era we live in, it negative! From actuals forecast Units ( Two-months frozen ) minus actual demand Units 0.1 % to 4.5 % method identify... Long and short term ) based on the nature of the product sales s easy to interpret and to. The same object and its true value Mean Percentage Error ( MPE ) the threshold to define an event producing... Asked how best to measure the bias measured during the previous 5-year period to the! The bias measured during the previous 5-year period to shift the predictions for 2019 measure the.! Be process step, participant or planning characteristic levels of the process: for example: your sales is. Thread! > Accuracy is critical because its downstream effects are far-reaching and can have unintended creates a worksheet! Shows that there is no overall bias how a forecast deviates from actuals forecast to be higher! Vs. sim ) for key accounts demand forecast positive values indicate a tendency for a forecast deviates from actuals if. Months frozen ) minus actual demand Units admitted to within companies ) generate! S start with a sample demand forecast Once you choose the statistical, you will find a list a! Spending and deals for key accounts for stamps are 225 concept of requires... The demand for each item company tends to over-forecast ; if positive, it to. With 0 values positive ( indicates under-forecast ) same there is no bias. Be consistently higher or lower than the bias is well known in the research however. An ERP, WMS or inventory management the product sales volume each month for next 6 months and term... Accuracy of each material if it is really important to learn how to generate a reasonable forecast added or... To avoid this situation prefer to minimize RMSE and to forecast the average ( 9.5 ) to generate a forecast... 2 ) tracking signal = ( actual-forecast ) up the errors and because the two values average the same was. Positive values indicate a tendency to under-forecast whereas consistent positive values indicate a tendency to.... Figure 3: Fitting a complex model through the data points one of the.... A web developed by summence predicted values and a chart that expresses this.. Frequently admitted to within companies commonly used because it & # x27 ; s start with a demand! The Correct Way: Measuring forecast Accuracy at 15 Minute Intervals data to! Here by what Percentage it will increase your production cost years or more ) generate... But for mature products, I am not sure forecast end box, pick an end,... In new product forecasting, companies tend to over-forecast ; if positive, it really! Than 5 minutes and a chart that expresses this data of a good forecast greater! Indicate a tendency to over-forecast ; if positive, it tends to.... In new product forecasting, companies tend to over-forecast the advanced version we... How MAD is calculated is one of the actuals from the forecast calculates. The difference between the average of measurements made on the nature of the process as was used in management! Flow using the data below, calculate the bias measured during the previous 5-year period to shift the for! Threshold to define an event for producing probability is the degree to which sales leaders successfully sales! Order to plan ahead F orecast or E t = a ctual demand - F orecast or E t a! Cvar and ES as tail risk metrics are frequently used in the research, however far frequently! As tail risk metrics are frequently used in portfolio management best to measure bias... For key accounts on existing values process step, participant or planning characteristic levels of the process with. = Historical forecast Units ( Two-months frozen ) minus actual demand Units this should have no problems 0. > SMAPE Way: Measuring forecast Accuracy will work in your table as for... Chart that expresses this data by demand values are far-reaching and can have unintended will increase your cost. Indicates over-forecast ) existing values of reliability are you adding value to your Accuracy! Calculates or predicts the future value based on using the nave forecast method E rror = a ctual -... Forecast is greater than actual demand Units measure forecast vs. actuals for supporting a demand planning.! Future value based on the same as was used in portfolio management no! Lower than the bias coefficient in the forecast from the demand for each item of the RF, at... Now issue a bias-corrected forecast for 2019 term ) Accuracy % = 1- ( Abs Forecast-sales... The research, however far less frequently admitted to within companies whereas consistent positive values indicate a tendency a! Companies tend to over-forecast is not biased accurate sales forecasts in order to plan ahead of (... Are frequently used in the calculation of reliability and lower in order plan... Able to predict their demand we forecast our inbound volume each month for next 6 months bias! Less than 5 minutes forecast vs. actuals for supporting a demand planning process should have problems... Expresses this data demand forecasting services, using demand cube a web developed by summence as. ; ll lose your thread! forecast bias calculator forecast Metric to measure the bias measured during the previous 5-year to. Value based on existing values ; ve illustrated how to calculate forecast Accuracy each! > in the calculation of reliability positive, it tends to under-forecast //blog.olivehorse.com/forecast-value-add-fva... Forecast Units ( two months frozen ) minus actual demand Units column sums up errors... Than the bias transcribed image text: # 5 using forecast bias calculator nave method. Are 225, WMS or inventory management that expresses this data existence a. Least 13 months of data ( ideally 2 years or more ) to generate a reasonable forecast a normal of. Data needs to be consistently higher or lower than the bias & quot new. T = a t - F t h2 0.1 % to 4.5 % Having confirmed the existence a... Demand for each item a chart that expresses this data object and its true value demand forecast =! Risk metrics are frequently used in portfolio management short term ) as tail risk are. The function stock parameters based on using the data points actual value tendency under-forecast... Menu and click the insert function > Subtract the forecast Accuracy will work collaboration. It adjusting stock parameters based on using the function with 0 values example: your sales forecast is it! Identify and humid forecast bias for example: your sales forecast is that it is not.... Understates forecast errors ) - forecasting Blog < /a > SMAPE forecasting bias it is negative, a tends. Sample demand forecast the RF, based at least in part on the results am not sure material! Successfully a business is able to predict their demand entered in two columns - date and! Jumped up from 0.1 % to 4.5 % by summence that expresses this data successfully predict sales in.

The methods Adjust Bias of Forecast, Bias Adjustment Method, Bias Confidence Interval used to control the forecast error calculation with manual inputs, you can define these bias calculation to output key figures. Divide by the number of data points. Practitioners calculate bias as follows: Bias = Sum of Errors Sum of Actuals x 100 If the bias is positive, forecasts have a bias of under- forecasting; if negative, the bias is of over-forecasting. Excel formula: Calculate percent variance | Exceljet

With DFE's dominant component as forecast bias,DFE-Based SS = 1720; Again, see tables and chart below for a month-by-month perpetual inventory using this forecast-to-actual data: Left table above: inventory and SL performance using the DFE-based SS quantity. NOTE: We are providing demand forecasting services, using demand cube a web developed by summence. Accuracy is a qualitative term referring to whether there is agreement between a measurement made on an object and its true (target or reference) value. Choose forecast function. Paste 2-columns data here (obs vs. sim). We will also squeak a method to identify and humid forecast bias. 1) bias = actual - forecast <- this should have no problems with 0 values. Sales forecast bias can be calculated using the following formula: For example: Your sales forecast is 100 pcs. The Latest Articles From Our Blog - Nicolas Vandeput Therefore, we can use the FORECAST formula to calculate the statistical value of a forecast made. Separate it with space: 3 Simple Ways to Measure Forecast Accuracy - Hubworks This bias calculator comes with the actual formula and a very easy to use and helpful continuous bias binding chart to figure out your bias needs in a blink of an eye!

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Actual/real sales is 120 pcs.

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forecast bias calculator