Another meter reading spreadsheet that needs help

[danb1203]

Hi everyone... Firstly i'll apologise for my lack of spreadsheet knowledge. This has been bugging me for days and I cannot come up with a formula.

Basically (and I hope I don't confuse anyone).. I want my spreadsheet to calculate the usage when I enter the figures.. but sometime I might not take meter readings for a few days. The problem with this is the formula I want must calculate from the last reading - which might not be the day before (you'll understand once you look at the spreadsheet).

Meter readings.xls

Have a little look.. let me know what you think.

Thanks.

Daniel

[ChemistB]

In D6 copied down and into other columns
=IF(ISNUMBER(C7),C7-INDEX(C$6:C6,MATCH(999^100, C$6:C6)),"")

Is that what you are after? You confused me with the value in D20, it doesn't match the pattern of other cells.

[danb1203]

Ahhhhh I absolutely love you! amazing! thank you so much.

This is perfect.