Entropy is the measurement of time and rate of change of entropy determines the duration of period at a particular moment in time.
The rate of change of entropy is increasing with time. The rate of change of entropy during the early days of universe formation was slower than what it is today. With rate of change of entropy increasing, length of period is decreasing along the time arrow. Thus previous billion years was a longer period than the succeeding one in the absolute terms.
Wowla! Shutter speed of god's camera is increasing.