The Football Association has said that FA Cup crowds have been at a 30-year high in recent rounds, figures it claims as evidence of the competition's renaissance.

Under previous regimes the FA admitted that its flagship knock-out tournament had stagnated in the face of competition from the Premier League and the Champions League and was in danger of losing relevance.

It considered a range of radical suggestions to reinvigorate the competition including scrapping replays and seeding, but under the current chairman, David Bernstein, and its general secretary, Alex Horne, the emphasis has been on accentuating its positives and less dramatic tweaks, including increasing prize money on offer.

Ahead of the semi-finals at Wembley this weekend, an innovation portrayed as a means of allowing more fans to see the games but also a crucial contributor to the national stadium's business plan, Horne said he was "really pleased" with the FA Cup this season and the extent to which the biggest clubs were taking it seriously.

"We've had some strong crowds again, the strongest crowds in rounds five and six we've had in 30 years, and we're on target for around 1.95m people attending FA Cup games," he said.

According to the FA the average fifth-round attendance was 32,566, the best since 1980, and the sixth-round average was 43,000, the best since the late 1970s.

Horne also defended the decision to hold the semi-finals – Millwall versus Wigan on Saturday and Chelsea against Manchester City on Sunday – at Wembley.

"When we designed the new national stadium, we knew we needed to put content in it. That's what is paying for the stadium. Over time we are paying off the debt we had to incur to build the stadium. Investing in Wembley is investing in football. It's a positive for all of football," he said.

The FA general secretary also defended the late-afternoon kick-off times. "We're now used to consuming our football in those time slots," he said. "It really works. Lunchtime kick-offs just haven't got the same appeal. The 5.15pm kick-off for the final was really successful. We added a couple of million viewers. It's a sensible compromise."