Hi all would greatly appreciate any form of help on the below. It's in one of my spreadsheets & am trying to work it out. Currently the sheet States March thou on the address bar it's got the below Formula. I don't now what it means & i'd like to change March into April. There is no spreadsheet named Index or Global Input sheet???Am very lost would love some help, & explanation as to what it means & does..

Cheers
Will

=INDEX('Global Input Sheet'!D12:D23,reportperiod)&" "