‘Jack” is being roundly ignored by New York radio listeners after the station dropped its famous oldies format last June, according to Arbitron preliminary ratings.

The unofficial monthly Arbitrends – a three-month rolling average that is now half Jack and half the former oldies format – show “Jack FM” in 17th place.

WCBS-FM was ranked ninth as recently as last winter when it still played oldies.

Jack, a trendy new radio concept known in other cities by names such as Bob, Doug, Ben and Hank, is a no-DJ format with a wise-cracking, pre-recorded announcer and a playlist that includes a wide range of pop music.

Elsewhere around the country, the unusual new format has been a big ratings booster – though not so far in New York.