Share prices for  National CineMedia plummeted more than 23% this morning to a multi-year low after the cinema ad sales company reported weaker than expected Q1 earnings — with a warning from CEO Andy England that “the first three quarters of 2017 will be challenging.”

He attributes that to weakening national ad sales and strengthening competition from digital video platforms.

The company underscored its concern by dropping its financial guidance for the full year: It expects revenues to fall as much as 6%, to $422.0 million. In February NCM’s worst case scenario for the year was a 0.5% drop to $445 million.

NCM lost $5.0 million in Q1, a 16.3% jump from the period last year, on revenues of $71.9 million, down 5.6%. Analysts thought that the top line would hit $74.1 million. The adjusted loss per share, at 8 cents, also was bigger than the 5 cents the Street anticipated.

“In addition to our national sales team experiencing a thin scatter market, there was a shift in overall ad spending, including a decrease in NCM’s two largest advertising categories — automotive and entertainment — which were down 15% year-over-year,” England told analysts.

One unnamed advertiser who spent $4.8 million in last year’s Q1 sat out this year — but is expected back later this year.

Calling 2017 a “transition year,” CFO Katie Scherping said that the company will cut “discretionary expenses” and make investments to promote “long-term sustainable growth.”

England says that while the ad market is “more unpredictable than I would like on a quarter-to-quarter basis,” he’s optimistic about NCM’s ability to attract buyers through its appeal to “millennial and Gen-C movie audiences.”

B. Riley’s Eric Wold  lowered his stock price target 12.5% to $14 — but calls NCM’s shares, now at about $9.00, “attractive ahead of improving operating trends.” In addition, AMC should complete its sale of NCM shares which the Justice Department required as a condition to approve the chain’s acquisition of Carmike Cinemas.

MKM Partners’  Eric Handler dropped his stock target 7.7% to $12, reflecting NCM’s lower financial estimates.