THEY JUST KEEP GROWING:

We've all seen the numbers: Health savings accounts just keep growing.

The still relatively new health savings vehicle has now grown to an estimated $18.1 billion in assets representing more than 9.1 million accounts. That's a 29 percent increase in both accounts and assets in just one year, according to research from investment consulting firm Devenir.

Devenir said the average account balance continues gradual growth. The average balance halfway through 2013 grew to $1,981 from $1,879 at the end 2012, roughly a 5 percent increase.

HSA contributions also are rising sharply. Total contributions to HSA accounts from June 2012 to June 2013 are estimated to have reached $16.7 billion, with accountholders retaining about 23 percent of those contributions.

HSA investment assets reached an estimated $2 billion in June, up 14 percent from the end of 2012 and 26 percent year over year. The average investment account holder has a $10,484 average total balance (deposit and investment account).

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