Part 2. MM4XL Tools > 1. Strategic Tools > Forecast Manager > 1. How To Run Forecast Manager > Page 1: Input Data
## Forecast Manager ### Page 1: Input Data In **Input Data** you can assign a **title** to the output report. The **Input data** range is the place where are stored the data to be fitted. This must be one or more columns, each of at least 5 numerical values larger than zero. *Note:* If there are zeros in your input data replace them with very small values such as 0,000001 or MM4XL warns on wrong input data. This is due to the optimization algorithm defined with formulae on sheet, which does not allow using zeros in some cases. The **Output range** can be either one single cell or multiple ones. In any case the output will start printing at the top left cell in the range. The **Data labels** range works the same way as the Input range one, but it allows for entering text as well as numbers, which will be used as row labels for your forecast. You can use, for instance, time labels such as Mar01, Apr01, and so on. *Note:* In the output report dates could be changed to numbers due to Excel format setting. If needed change your Excel settings in Extra, Options. The **Forecast horizon** spin button defines how many time periods ahead to make projections after the last known value. When forecasting short-term, horizons behind 12 periods are to be seen as medium-term rather than short. In order to produce useful results it has been set the limit (1:2) to the horizon one can forecast further, so if you are using a series of 20 periods you can project up to 10 periods ahead. If your data have column **labels in first row** check the corresponding option in the frame on the right side of the window. Those labels are used for distinguishing between series when running a multi-series forecast. Check the **Show hidden sheet** option if you want to see the sheet where MM4XL stored all data used to produce the forecast for each selected method. This is also the place where you can open the black-box and see actually what formulae were used with each forecasting method. The **Remove formula** is the option you select for replacing formulae with numbers in the hidden sheet. *Tip:* Formulae cost resources, so when doing multi-series (batch) forecast check the **Remove formula** option and Forecast Manager will run faster. In the field **Special events** select with the mouse the range where are stored text labels used for identifying the kind of special event affecting time periods. This range must be the same size of the Input data range, but in this case blank cells are allowed and are even required for time periods when no event is being assumed. List of constraints to page Input Data: **Option** | **Constraint** | Input range | Min 5 rows of values. No zeros, blank cells, or text strings. | Data label range | Same size as input range. No blank cells. | Special events range | Same size as input range. | Forecast horizon | Larger than zero. Max horizon < (number of input periods / 2). | Input range | Max 230 columns of data. Max number of rows limited by Excel only. | |