****** research finds significantly more men’s than women’s tennis seen on Centre and No 1 since 1993 Wimbledon is behind the times when it comes to gender parity with a distinct lack of progress on affording women equal time on the championships’ main show courts over the past 25 years, it has been claimed.The novelist, campaigner and tennis fan Mark Leyland found that in every year from 1993 to 2017 more men’s than women’s matches were scheduled on Centre and No 1 courts with an average of 61% men’s and 39% women’s matches.Taking into account that men’s matches are longer than women’s, it suggests that two-and-a-half times more men’s than women’s play has been seen on these courts during the period covered, he says – and the discrepancy shows little sign of narrowing.Leyland calculated last year’s split as 58% to 32% in favour of men.He had released research before the tournament showing an overwhelming gender bias in 2015 and 2016.His latest research, shared exclusively with the Guardian, examines the imbalance over a longer period.To illustrate the lack of progress, Leyland highlights the case of the women’s No 4 seed, Elina Svitolina, who played four matches without ever being scheduled on a main show court last year, while the men’s eighth seed, Dominic Thiem, played his first three matches on No 1 Court. He said: “The 2017 movie Battle of the Sexes portrays representatives of the 1970s world tennis authorities trying to justify vastly different levels of prize money by claiming that men’s play was more exciting and better to watch.The authorities at Wimbledon make no such claims to justify their own inequitable system, insisting that they value fairness and do not intentionally favour the men.“They persist in blaming the imbalance on the complexities of a system which has long since achieved equality at the other grand slam tournaments, an argument which defies all logic.But it may be felt that their actions, in scheduling more men’s than women’s matches on their main show courts every year for more than a quarter of a century, speak louder than their words.” After Leyland’s analysis was published before last year’s tournament, there was more controversy when, on the second Monday, all four men’s matches were scheduled for the main show courts but only two of four women’s matches.That prompted Andy Murray to join those calling for an equal split.The latest statistics have been published as Serena Williams, winner of 23 grand slam singles titles, prepares to return to the tournament, which starts on Monday 2 July, for the first time since giving birth.Williams and her sister, Venus, winner of seven grand slam titles, have complained in the past of being relegated to smaller courts and Leyland’s analysis suggests they were right to be disgruntled.He found that in the decade from 2007 to 2016, over the first four rounds, Roger Federer played 31 times on Centre Court (84% of his matches), six times on No 1 Court (16%) and never anywhere