Sumif based on dates not working

[odonovanc]

Aug-16

01/31/16 02/28/16 03/31/16 04/30/16 05/31/16 06/30/16 07/31/16 08/31/16 09/30/16 10/31/16 11/30/16 12/31/16 4 months
Charges 375,743 393,931 514,907 490,482 480,772 479,377 507,250 465,559 463,607 452,198 389,260 424,965 0

So in this example, Aug-16 is in cell AG1. The 0 is where I am trying to write a sumif. I want to sumif the charges line (U5:AF5) if the date in AG1 > the dates listed in (U2:AF3). I keep getting 0. Please help

 

[steve the fish]

Presuming AG1 contains a valid date then:

=SUMIF(U2:AF2,"<"&AG1,U5:AF5)