Need to select only certain months' of data

[fogs88]

Hi,

I have a spreadsheet with daily data from 1900 to 2010 with two columns, one with the date, the other with precipitation values. What I need to do is to only select the data from 1 April - 30 September of each year.

I'm sure there must be a way to select only certain months but I can't find out how to do it and it would take hours to do it manually seeing as I have 80 spreadsheets needing the same treatment! If anyone could help I'd be very grateful! I've attached one of the files in case I've not been very clear...

Thanks,
Lucy