python pandas; how to minus 1 unit to the BEG column? could you provide codes for it?

So that I could get the output for example (8,9) instead of (9,9) when I print(SAMPLE).

A B C D E 2 RT BEG END LEN A/N VARIABLE DESCRIPTION 4 H 1 1 1A RECTYPE Record Type 6 H 2 8 7A SERIALNO Housing Group Quarters (GQ) Unit Serial Number 8 H 9 91A SAMPLE Sample Identifier 10 11 2A STATE 10 11 2 A STATE State Code State Code 10 H 11 H 12 13 H 14 H 15 H 16 H 17 H 12 12 12 12 12 1A 1A 1A 1A 1A REGION REGION REGION REGION REGION Region Code Region Code Region Code Region Code Region Code 12 12 18 13 13 13 13 13 19 H 20 H 21 H 22 H 23 H 24 H 25 H 26 H 27 H 28 H 1A 1A 1A 1A 1A 1A 1A 1A 1A 1A DIVISION DIVISION DIVISION DIVISION DIVISION DIVISION DIVISION DIVISION DIVISION DIVISION Division Code Division Code Division Code Division Code Division Code Division Code Division Code Division Code Division Code Division Code 13 13 13 13 1313 13 13 13 13 an