Sum of working hours

[dudescuman]

I need to create a table of hours of work all year long, where every day I must sum the last 28 days.
How can I get sum of the hours of work each day?
For exemple.. like in the file... from April 18 untill Mai 16 (marked with red) I have a total of 15 58 hours. Next I need a sum from April18 untill May17.
Thanks

[Jamesr571]

Hello,

I cannot open the file, can you resave as .xls?

[Pepe Le Mokko]

Hi James

if you want to, you can download a free converter from MS to convert xlsx to xls

EDIT although the OP's file seems a bit weird to me...

[dudescuman]

Ohh.. sorry. I can not save right now.. I am at work, and here I have Linux... and I get a error when tring to save xls. Immagine a table with every mount in colums, and on rows are days.... In every day I get a numer of hours of work.... and I need a sum of hours of work from April 18 untill Mai 16. next sum.. 19 april untill Mai 17, next 20 april untill Mail 18 and so on..