Figures obtained through Freedom Of Information requests show 116,601 fixed penalty notices were handed out in 2011, down from 121,624 the previous year, a drop of just over 4%
The figures were released by car insurance provider Swiftcover.com, but it says the reduction in the number of notices issued could be due to a reduction in the number of parking attendants rather than fewer offences being committed.
The number of wardens fell from 118 in 2010 to 116 last year.
Generating potentially as much as £2.9million – down £125,000 on 2010 – for Glasgow City Council in 2011, the attendants issued an average 1005 notices each over the year.
This was more than Wolverhampton City Council, whose 32 officers each averaged 579 parking fines, but less than Liverpool City Council's 56 officers, with 2616 issued per officer in 2011.
One in every four penalty notices issued in Glasgow last year was disputed, of which 22% were successfully overturned.
The Evening Times revealed last August that Glasgow was among the strictest in Scotland when it came to parking ticket appeals.
The city council was second toughest, with East Ayrshire the most hardline area, letting off only 20% of drivers who challenge their ticket.
The value of a penalty notice is £60, but this is reduced to £30 if the driver pays in full within 14 days of the ticket being issued.
Robin Reames, chief claims officer at Swiftcover.com, said: "Shortage of parking spaces has become a huge issue in towns and cities across the UK in the past five to 10 years, but this does not excuse illegal parking.
"Although it might be an easy option to park on double yellow lines for a short time, it is potentially dangerous, as well as being illegal, and can result in a fine.
"Furthermore, if your illegally parked car is a hazard and a moving vehicle crashed into it, an insurer could in theory request up to a third of the bill from the at fault motorist."
A city council spokesman said: "Fewer penalty charges are being served for a variety of reasons, including increased compliance by drivers, which is to be welcomed."