I am trying to find a way to subtract the values of two labels, like this: $45 - $20 = $25.
Shopping Cart Total: $45 (Label6_8)
Current Dragon Ticket: $20 (Label6_6)
To determine your remaining Dragon Ticket balance, subtract 'Label6_6' from 'Label6_8':
$45 - $20 = $25 (Label6_4)
Your Dragon Ticket balance is now $25 (Label6_4).