After 4 years of consecutive growth, Colorado's graduation rate failed to improve in 2015. Meanwhile, the dropout rate grew for the first time in almost a decade.

According to data released by the state Thursday, public schools statewide graduated 77.3% of students in Spring 2015 - the same rate as 2014.

For the first time since 2006, Colorado's 2015 dropout rate increased to 2.5%. That means public schools saw 568 more students drop out in the 2014-15 school year than the previous year.

Judith Martinez, the Colorado Department of Education's director of dropout prevention, says the department will further analyze the data in coming weeks to determine what may have caused the dropout rate increase.