The asset management and investment services sub-sector grew at an annual rate of 8%, compared to 5% per year for the finance, insurance, and real estate industry from 1997 to 2013. Asset management and investment services are small components of the sector, about 5% of the financial industry, in terms of sector GDP. The sub-sector, however, is more cyclical than the overall financial sector. It declined more than the overall financial sector in the last recession, making the companies that operate in asset management and investor services sub-sector more risky. Here are some of the best asset management and investment services TheStreet Quant Ratings says you should consider looking at. Number 3 is SEI Investments. With an 'A+' rating, the company's strengths can be seen in its revenue growth and increase in net income. 2nd is, Invesco. This rating is also an 'A+.' Invesco thrives in its solid stock price performance and notable return on equity. Number 1 is BlackRock. With an 'A+' rating the company flourishes in its revenue growth and expanding profit margins. TheStreet Ratings are algorithmic stock picks based on 32 major data points. S&P 500 stocks rated 'buy' yielded a 16-and-a-half-percent return in 2014, beating the S&P 500 Total Return Index by more than 300 basis points. For the full reports on these stocks, you can check out TheStreet.com/QuantRatings.