The current earning only update if you made less than 100$ on the previous previous month. And it does get carry forward on next month if it havent reach 100.
So (19.99 + 29.99) * 0.88 = 43.9824
Exceptionally at end of december, everything will add up even if you havent reach 100$ and will be paid on the following month,
So it should be 119.96 * 0.88 that will be sent to you at the end of January.