The Ginnie Mae servicing business remained concentrated in a group of large lenders at the end of 2005, with Wells Fargo Home Mortgage holding the biggest chunk of the market. Wells was servicing $89.5 billion of loans securitized through the Ginnie Mae program as of Dec. 31, or about 22.0 percent of the total market. That was down slightly from the company’s Ginnie servicing volume at the same time in 2004, but Wells did a… [One data table included]