Hi,
It looks like your view is showing 30 min staffing intervals, so for the 30 mins when they are on a 15 min break you have 7 staff for 15 mins and 0 for 15 mins, so ave staffing for the 30 mins is 3.5 - rounded to 4.
I think....
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Dave Tiltman
RCN, Royal College of Nursing
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