A cracked rail slowed down Metro’s Red Line for about five hours on Thursday, in the 26th case this year of a broken rail on the transit system, according to Metro.

Metro has been dealing with dozens of these cracks in recent years. Last year, the agency had 49 cases, and in 2010, 33, while 2009 had 19 and 2008 had just seven cases. This year the numbers appear to be tempering, though still presenting challenges for the agency — and its riders.