ORLANDO, Fla. -- The NFL received its highest grade for diversity hiring practices but still has work to do.

The annual report by The Institute for Diversity and Ethics in Sport on Thursday gave the league its third consecutive A grade on racial hiring and its first C-plus for gender hiring -- it drew C's the past three years. The combined B score of 82.3 percent is tops for the NFL.

Richard Lapchick, the main author, attributes the improvement to what he sees as a push from NFL commissioner Roger Goodell and his key managers.

"I think that it's definitely all the commissioner can really do in addition to encouraging inclusion on the teams," Lapchick said. "He can't influence their hiring or shape the specific direction of teams. But I think by bringing in diverse voices that is definitely his thinking in the league office."

Last spring, the NFL launched the Women's Interactive Network to help accelerate career advancement for women in the NFL. It joined the NFL Diversity Council (established in 2002) and six other programs aimed at fostering greater diversity.

According to Thursday's report, the league office has 28 women and people of color working at or above the vice president level, an increase of 8 percent. That breaks down to 17 women (up 13 percent from 2011), with the number of people of color at or above the vice president level remaining constant from a year ago.

At the team level, the percentage of people of color with senior administrator positions remained constant in 2011 at 16 percent. The total senior administrator positions held by women fell from 21 in 2010 to 20 in 2011.

Amy Trask, of the Oakland Raiders, remains the only female president or CEO of a team in the NFL, a position she has held since 2005. There has never been a person of color serving as president or CEO of a team in the history of the NFL.

"It's easier to change numbers at entry level or even managerial position, but teams are seeing that the commissioner and people that report to him are putting women and people of color in most senior positions," Lapchick said. "They're going to see that as a manager or director and see it's important to the commissioner and open their hiring processes more. It may eventually still be a white guy, but they are at least opening the process more."

On the field, half of last season's playoff teams had either an African-American head coach or general manager.

The NFL is enjoying historic gains in racial diversity among its head coaches, with eight head coaches of color beginning the 2011 season -- a league record. The number dipped to six to begin 2012, with Carolina's Ron Rivera remaining the NFL's only Latino head coach.

But those losses come as the number of African-American general managers increased from five in 2011 (16 percent) to six (19 percent) to begin 2012. This comes after Jerry Reese, the first African-American GM to win a Super Bowl in 2008, earned his second title last season.

Lapchick pointed to a milestone that may have important implications: Shahid Khan, a Pakistani-born American businessman, became the league's first majority owner of color.

"Clearly, on the one level, it's something a lot of people have been waiting for," Lapchick said. "All these things are incredibly symbolic for the game. And people of color that have aspirations to be included definitely look at that as being very important."