Sumif - Date Range

[HelpfulMan]

A	B
400	13/3/15
200	20/3/15
180
310	29/4/15
750	21/3/15
384	15/3/15
900

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</tbody>

The above is an example of my current problem. I'm trying to arrange for a SumIf formula to calculate the value of Column A within a specific date range (i.e. how many sales from A to be completed between the 13th-20th?). There will be some blank ones for incomplete sales.

Any help or formula building suggestions would be appreciated!

 

[sericom]

=sumifs(a1:a7,b1:b7,">=13/3/2015",b1:b7,"<=20/3/2015")