index or match two columns in different workbooks

Hi

I have one column with dates as below

workbook one / Workbook two

a Column / C column /b column

07 may /0 /08 may
08 may /2 /08 may
09 may /0 /30 dec
10 may /0 /31 dec
. /. /.
. /. / .
. /. / .
29 dec /0 /.
30 dec /1 /.
31 dec /1 /.

I need a formula in workbook one matching dates in A column and showing results as in C column.
Is there any body that can help me.
Many thanks in advance

Thanks for quick reply,
Attached here is an excel file simply explained.
Thanks

Thank you popipipo,
It does what I need perfectly.
Please let me know if there is any way I can rate you maximum
Sorry I use this forum second time after a long time and I am not sure how rating works
Again Thanks a lot