MIAMI – The NFL has kept a steady number of black head coaches, while slightly increasing the ranks of Asian and Latino players, earning a B+ in an annual diversity study Wednesday.

However, the league didn't get a grade for gender diversity for the fourth year in a row. The NFL is the only pro sports organization that refuses to share its league office data with University of Central Florida's Institute for Diversity and Ethics in Sports, which also conducts annual studies on the NBA, Major League Baseball, WNBA, pro soccer and college athletics.

The last time the NFL shared its data, for the 2004 study, it received a D+ for gender hiring practices.

“We prefer to focus on our own initiatives to enhance diversity and inclusiveness in our workplace,” NFL spokesman Greg Aiello said.

Richard Lapchick, report author and head of UCF's diversity institute in Orlando, Fla., said the league data would probably better than the NFL's most recent grade. At the team level, 18 percent of senior administrators were women for 2007, along with 11 percent of vice presidents, according to the newest report.

Lapchick compiled that information from media guides for the NFL's 32 teams. He goes through the same process for other sports, then usually sends a compilation to the league for feedback and corroboration. All but the NFL respond, he said.

However, Lapchick gives the NFL credit for its own improvement initiatives, like the Rooney Rule. The change, approved in 2002, requires teams to interview at least one minority candidate for each head coaching vacancy.

The NFL has six black head coaches and five black general managers entering this season, the same as 2007. There were two black coaches in 2001, six in 2005 and seven in 2006.

Four new head coaches, all white, were hired entering the 2008 season.

“I don't read anything into that,” Lapchick said. “With all leagues on any given cycle, it can turn out that way or it can turn out that a disproportionate percentage were coaches of color that were hired.”

In the 2007 season, 66 percent of NFL players were black, a one point decrease from the previous year. White players continued to comprise 31 percent of the total, but the difference was made up by a small increase in Latino and Asian players.

For assistant head coaches, in 2007 the league sustained the previous year's record with 38 percent of the jobs filled by minorities.