NEW YORK - Transit riders who use the C train may get frustrated by delays and service changes, but at least now they will know when the trains will arrive.

The Metropolitan Transportation Authority says countdown clocks have been installed at all C train stations.

The line runs from Washington Heights-168th Street in Manhattan to Euclid Avenue in Brooklyn.

This does not mean the clocks have been put in at all A and E train stations.

It's not clear when those will have the system installed.

The MTA's goal is to have countdown clocks put in every lettered-line station by sometime next year.