"gloomy years" is correct and usable in written English.
You can use it to refer to a period of time that was characterized by sadness. For example: "The 2000s were a series of gloomy years for the country."
The marriage of Sobieski's daughter Kunegunda to Maximilian II Emanuel, elector of Bavaria (1694), was the only bright spot in these rather gloomy years.
Yet he is the only candidate brave enough to advocate the "rupture" with its past that France needs after so many gloomy years.
The first draft of a long piece on California geology took two gloomy years; the second, third, and fourth drafts took about six months altogether.
IN THE 1950s Heinz Mack and Otto Piene were energetic graduates of the Düsseldorf Academy of Arts, tired of the destruction wrought by the second world war and of the gloomy years that followed.
Now, however, the new administration of Hassan Rouhani is taking steps to open up Iran to foreigners in an effort to improve its international image after the gloomy years under Mahmoud Ahmadinejad – and to bring in much-needed foreign currency to an economy reeling from years of sanctions.
The quarter's revenue growth is a flicker of positivity in what have been multiple gloomy years for the company.
