Perhaps numbers never do reveal the full story, but they tell a large part of it. Every Friday, The Numbers Game will take a look at statistics from the present and the past, busting myths and revealing hidden truths:

They're the unsung heroes of cricket. If umpires can complain that they come into the limelight only when they commit an error of judgment, then the same argument applies - perhaps to a slightly lesser extent - to wicketkeepers as well: while a brilliant catch will not go unappreciated, a crucial mistake will probably stick in the memory much longer. Kiran More's miss off Graham Gooch at Lord's in 1990 was the difference between him making 33 and 333; Ian Healy's lapses against Brian Lara and Inzamam-ul-Haq at Barbados and Karachi converted victories into defeats. These are just three instances - jog your mind further and a whole host of such instances will emerge.

Statistically, too, it's much tougher to convert a wicketkeeper's performances into numbers which can be compared and rated. The tally of catches taken or stumpings effected is the most obvious stat, but it glorifies those keepers who are fortunate to have quality bowlers who induce edges and beat the batsmen, and belittles the ones who, unfortunately, don't have such champion bowlers in the side. Syed Kirmani had 198 dismissals from 88 matches, while Jeff Dujon raked in 272 from 81 - do those numbers in any way suggest the relative wicketkeeping skills of Kirmani and Dujon?

The other way, then, is to look at the number of byes conceded per match. This method, again, is far from satisfactory, for some bowlers are much tougher to keep to than others. With a minimum qualification of 20 Tests, this table throws some unlikely names at the top: Paul Downton, England's wicketkeeper in the mid 1980s, and Khaled Mashud, Bangladesh's current gloveman, take the first two spots. And the wicketkeeper with the highest byes-per-match figure is Don Tallon, who was a legend behind the stumps for Australia in the 1940s and early 1950s. His stat of 13.90 byes per Test is quite clearly a reflection of just how difficult it was to keep on uncovered pitches.

And there's something interesting about Dave Richardson's stats too - in 42 matches, he has 152 dismissals while having conceded only 139 byes, making him the only wicketkeeper with more than 20 Test caps to have more dismissals than byes conceded. Others who have played fewer than 20 matches (and more than 10) but have achieved the feat are Denis Lindsay, the South African (15 Tests, 56 dismissals, 20 byes) and Lee Germon, the former New Zealand captain (12, 29, 24), while England's Chris Read has 35 scalps and an equal number of byes in 11 matches.

A better system to rate wicketkeepers, though, would involve looking at chances missed as a percentage of dismissals made, and then bring in byes conceded and runs scored to offer a complete picture of a wicketkeeper's contribution to the team. Wisden Cricinfo began recording ball-by-ball data for all international matches from September 2001; hence such an analysis can only be done for the last four years.

The calculations have been done in the following manner - subtract the byes conceded from the total runs scored by a wicketkeeper, divide by the matches played to get a per-Test figure, and then add the percentage of chances taken to arrive at an overall rating. The results are interesting: Adam Gilchrist heads the list, which is no surprise, while Kumar Sangakkara comes in next, largely due to his exceptional batting record (66 runs per match). At No.3 position is Tatenda Taibu. No-one doubts his wicketkeeping ability, but his stats are helped by the fact that Zimbabwe bat twice in most games and field just once, allowing him more opportunities to boost his run-tally. (If, instead of runs scored, batting average is considered, then Taibu is in sixth place, behind Gilchrist, Sangakkara, Rashid Latif, Alec Stewart and Mark Boucher.)

Geraint Jones misses out on the top ten with a rating of 109.02 (803 runs, 197 byes, 78.72% catches taken). Of the 14 wicketkeepers who make the cut of ten Tests during this period, India's two representatives - Parthiv Patel and Dinesh Karthik - bring up the rear, and their numbers tell a sorry story: Parthiv spills, on an average, one out of every three chances that come his way (46 taken, 23 missed), while Karthik's undoing has been the high number of byes conceded - 139 in ten Tests - and the lack of runs scored - only 245.

The above method isn't perfect either, and is open to debate - should runs scored be considered at all, and if yes, then should it be given a lesser weightage? (Write in, if you have a better suggestion.) By this method, though, it's certain that most of the earlier wicketkeepers would not fare well, simply because their batting averages are much lower than the current lot's. Gilchrist best illustrates the modern wicketkeeper, who must not only be skilled behind the stumps, but also competent enough to spend long periods in front of it with bat in hand. The table below shows just how wicketkeepers have improved their batting over the years - in the 1910s, they averaged 13; today, those digits have been reversed.

In fact, of the 20 wicketkeepers who average more than 30 in Test cricket (minimum qualification ten matches), eight of them played all or most of their cricket after 1990. Among the keepers of yesteryear, Les Ames's average of 43.40 in 44 Tests is the highest, while Clyde Walcott, who kept wicket in 15 Tests, and South Africa's Denis Lindsay averaged in the 40s too.