To find the common difference \( d \) of the arithmetic sequence, you can subtract any term from the subsequent term.
Using the first two terms: \[ d = 12 - 32 = -20 \]
To confirm, you can also check with the next pair of terms: \[ d = -12 - 12 = -24 \]
So, the common difference \( d \) of the sequence is \( -20 \).
Thus, the common difference of the arithmetic sequence is: \[ d = -20 \]