The share of first-time homebuyers in the market fell to 27% in December, according to the National Association of REALTORs, the lowest level since the trade group began tracking them in 2008.

Factors such as high student loan debt, less-than-perfect credit, low employment and wage growth, and double-digit growth in home prices last year are squeezing first-buyers out of the housing market where they have traditionally held a 40% share.

“First-time home buyers tend to purchase lower-priced homes, but they’re facing competition for those homes from all-cash investors,” according to NAR’s Daily Real Estate News. “Cash purchases accounted for 42.1% of all U.S. home sales in December, up from 38.1% in November, and up from 18% a year prior, according to RealtyTrac.”

Other factors hampering first-timers are tighter credit requirements, including mortgage lenders requiring higher down payments. Also, FHA loans, a source for low down payment loans for many new borrowers, have lost market share in the wake of higher premiums and fees that have made FHA loans less attractive.

Last November, NAR reported that tighter mortgage lending standards are keeping qualified buyers, particularly singles and first-timers, out of the home-buying market.

According to the 2013 Profile of Home Buyers and Sellers, the overall market share of single buyers fell from 32% in 2010 to 25% in 2012 and 2013. First-time home buyers slipped to a 38% market share in the past year from 39% in 2012.