The number of investment advisor clients rose 9.6 percent to 25.5 million while total regulatory assets under management climbed 11 percent from July 2012 to April 2013, the Investment Adviser Association and National Regulatory Services reported Thursday.

The groups attributed the RAUM hike to a rise in the stock market and the client increase.

For the same period, the number of SEC-registered investment advisors rose slightly from 10,511 to 10,533, the two groups said in a study.

The industry remains very much a mom and pop operation in terms of employment, with 73 percent of the businesses having 10 or fewer employees in investment advisory matters and 73 percent of firms managing less than $1 billion.

The 99 advisory companies in charge of over $100 billion each account for less than 1 percent of the total number of registered advisors, yet they are responsible for more than half of RAUM.

The concentration of assets in the biggest firms became more substantial in the past year, growing from 48.9 percent in 2012 to 50.9 percent in 2013.

In another finding, the number of investment advisors reporting custody of client cash, bank accounts and/or securities rose slightly from 30.4 percent to 31.1 percent.

There was virtually no change in the percentage of advisors receiving compensation in all categories ranging from commissions to performance-based fees to percentage of client’s RAUM.

To see the full study, go to: