What is the purpose of a trailing minus sign?

Question

I cashier at a grocery store and the POS system we use (SurePOS by IBM/Toshiba) uses trailing minus signs for all of its representations of negative numbers.

Examples:

• Coupon being rung up:

MC SCANNED COUPON 1.50-

• Change due when a check is written for $20 over the amount:

BALANCE: 20.00-

What is the reason for the trailing minus sign, why not -1.50 instead?

Answer 1

It seems to me that this allows for a quick scan down the right-hand column to see which items are negative. All minus signs will be in the same column. If the minus signs are on the left-hand side, then they won't necessarily line up.

Compare:

A 15.00-

B 1255.50

C 0.10-

D 175.00-

to

A -15.00

B 1255.50

C -0.10

D -175.00