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If there is a start date and the install date is blank The : it will use the start date of the machine to the last date of the meter count for each meter
If there is an install date, then it will use the Install date to the last date count for each meter.
Convert.ToDecimal(( latestCountDate - machineInstallDate).TotalDays) / 365M * 12M;
Eg Machine XXX has a start date of 16th December 2014 and no install date.
To find the last meter count for this machine colour meter, click on the Counts Tab and it is 20th July 2020
From the 16th December 2014 to 20th July 2020 = 2043 days (approximately) Do not include the last day of the count.
You can use the web calculator https://www.timeanddate.com/date/durationresult.html2043days /365 = 5.597 * 12Months = 67.167 days
Look at the Count Inc eg countinc for Colour meter = 279539
CountInc 279539/67.167 days = average meter count of 4161 (in the average monthly count field for the colour meter)
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