Price appreciation gain convention in CFA Level III

CFA Level III Fixed Income
#1

Hi folks, I have seen two conventions in CFA III curriculum for price appreciation gain (in a roll-down scenario), both for bond.

  1. Gain = (Current price - previous price) * notional (Reading 13, Example 3).

  2. Gain = (Current price - previous price)/previous price * notional (Reading 14, Example 26)

Anyone knows which one to use in the exam?