There is something wrong on SP page. Data is changing after we enter data into cell and click save.
For example: we added new position and selecting role then enter the value 10 person days for Jan 15 (screenshot 1). Forecast value is changing from 10 person days to 20 person days (screenshot 2). It is displayed 1.43 when we click position (screenshot 3). Please find attached screenshots.
We enter value as FTE, Hours for different date ranges Years, Quarters, Months, Weeks and it is the same.