From your link:
Young debtors aged 18–29 account for 14% of all insolvency filings, up from 12% in our previous study. 
Senior debtors aged 60 and over now make up 12% of all insolvencies, continuing the growth trend begun in 2011.
Student debt is a factor in 15% of all insolvencies, up from 13% two years ago.
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While student debt is a rising factor, the listed groups' percentage increase can be mostly accounted for by the decrease on overall insolvencies. Looking at the more detailed tabs, the comparisons are still % of debtors rather than number per capita. So the study and report is written to be alarmist, rather than analytical.