The credit ratings for Koreans in their teens and 20s rapidly declined after the global financial crisis due to factors including reduced employment and student loan delinquencies, data collected from the Korea Credit Bureau revealed Wednesday.

The average credit rating for each age group of 500,000 randomly selected credit users showed that teenagers’ average rating deteriorated from 3.96 in the first quarter of 2008 to 5.44 in Q1 of 2013, according to the Bank of Korea.

Ratings for those in their 20s also weakened from 5.14 in Q1 of 2008 to 5.62 in Q2 of 2013.

The KCB classifies credit ratings with a score of 1 to 10, where 1-4 is considered a good credit score and 7-10 is poor.