Nick,
the data will look like this before the use of keep if command
item_code exp_val sales_val
6 75 .
1 100 6250
4 60 30
2 60 1
3 52 15
9 407 .
4 60 3
9 738
2 120 2
2 100 5
after using the keep if command and merging back
state_code_6 exp_val_6 sales_val_6 state_code_2 exp_val_2 sales_val_2
6 75 . 2 60 1
. . . 2 120 2
. . . 2 100 5
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