Now, we might suppose that the Earth could continue at that rate forever, with each day being 86,400.00175 seconds (average over several decades). The would be zero deceleration. But in fact, the Earth is decelerating. In about 100 years, we can expect that the day will be 86,400.00375 seconds long. Then leap seconds will have to put in about every 267 days (average). And in 1000 years from now, the day will be 86,400.02175 seconds long, and leap seconds will be needed every 46 days (as always, on average). (The detailed situation is a bit more complicated.) Some people are worried about this — see the second link below.

There is a graph of the "excess" length of day at the first link. Look for the graph labeled "BullA LODS".

For a more technical paper, try the third link.