Current Quantity: it is calculated as difference between charged quantity and used quantity of a feed in the period between the feeding starting date and the beginning of feeding period. The charged quantity in stock is determined by considering the movements done (loading, unloading, settlement or corrections), while the used quantity is calculated from the data of the recipes fed before the feeding period starting date. If a starting date is not defined for the feed administration, the date when the first feed loading happened will be considered as starting date. The calculation of the used quantity uses the following operations:
1) for each group of animals, the feeding period is divided into intervals according to the changes of the recipes fed: every recipe coincides with an interval that starts with its modification date and ends with the modification date of the next recipe fed;
2) used quantity for each group is calculated, accounting the feed quantity in each recipe and multiplied for the related number of heads and the days of the interval;
3) the total quantity used in the farm is obtained by adding the due contributions to each group.
By modifying the current quantity in the As Fed column, the entered value, added to the quantity potentially used, will be saved as correction to the loaded quantity in stock, with the same date as the feeding period starting date. In the absence of a loaded quantity in stock, the used quantity will not be calculated; for the same reason the balance availability columns and usable quantity will not be shown.
Required quantity: it represents the use of each feed during the feeding period.
For each group the period is divided in intervals concerning each recipe fed. The feed quantities in each recipe are multiplied for the number of animals and for the corresponding days of the interval. Contributions due to each group are added in order to obtain the total quantity required for the whole farm. The daily required quantity is calculated as average on the number of days of the feeding period.
Balance Availability: the first too columns show the quantity of each feed at the end of the feeding period. If the balance at the end of the period is negative, the current amount will not be enough to cover the whole feeding period.
The third column shows the number of days for which the current quantity will be enough to cover the requirements (daily needed amount). The fourth column points out the date in which the current quantity will run out; this is calculated by adding the number of days shown in the previous column to the feeding period starting date.
Usable Quantity: represents the maximum amount that can be fed daily during the feeding period taking into account the current quantity. It is calculated by dividing the current quantity by the days of the feeding period. If the current quantity is not enough to cover the whole feeding period, the usable quantity will be lower than the daily necessary quantity feeding the current recipes; for this reason, it will be enlightened to signal the need to purchase that specific feed or change the recipes to include proper amounts.