auto populate and substract

[apgmin]

cell A1 has the month which has to be manually filled

Cell A2, A3,A4... has the dates of that month, Can we have a formula where the dates are autofilled depending on the month mentioned in Cell A1 ( as some months will have 31 days and some 30 days )

Secondly in Cell B2, B3, B4.... we mention the electricity meter reading as on morning of that day ( the date which is mentioned in column A for that particular cell )

In cell C2,C3,C4... i have put a simple formula of substracting the earlier day meter reading in column B to the current reading, this tells me how much electricity consumption has been done on that day for the last 24hrs.

But if the earlier cell is not filled in column B due to holiday and is blank then the cell in column C it should take the previous filled value from the cells above in column B

Please help

 

[davesexcel]

=if(b3="",b2,b3-b2)

I think I have it.

 

[footoo]

In cell C2 : =IF(B2="",0,B2-SUM(C$1:C1))

What is entered in A1 ?
A date, or a month number, or "Jan", or "January", or what ?

 

[davesexcel]

Ha! sorry, I forgot I had posts starting from the bottom and go up!

 

[davesexcel]

Place the 1st of the month in A1
Enter this in A1 and drag down to A31

=IF(A1="","", IF(DAY(A1+1)=1,"",A1+1))