This is what I get:
POST: array (
'Test_Product_1' => '159',
'Test_Product_2' => '456',
'Test' => '789',
'action_button' => 'Save Sales Targets',
)
This looks fine, the only strange thing is that there are underlines between the words whereas these should be just spaces ('Test_Product_1' instead of 'Test Product 1'), although it might be normal that this is how they are echoed.
However, the script I posted returns the value only for 'Test', and doesn't return anything for 'Test Product 1' or 'Test Product 2'.
Thanks indeed for looking into this.
If looking at the application helps, this is the link:
http://theplumber.whsites.net/test/theplumber. Log in as "admin", "admin", then go to the Control Panel and choose Sales Targets.