The number of people trying to quit smoking via NHS services has roughly trebled in the last decade but success rates have fallen, figures show.

In 2010-11, there were almost 788,000 “quit dates” set with NHS stop smoking services, with almost 384,000 successful attempts.

In 2001-02, there were just 227,000 quit dates set and fewer than 120,000 successful attempts.

People may be successful on their first try, or can set further quit dates throughout the year if their first attempt fails.

The overall success rate is now 49 per cent, the same as the previous year, but down on the 53 per cent recorded in 2001-02, according to the data from the NHS Information Centre.

People are counted as successful quitters if they are still not smoking four weeks after their quit date.

Tuesday’s report showed the total amount spent on England’s NHS stop smoking services in 2010-11 was £84.3m, almost £500,000 more than in the previous year and almost £60m more than a decade ago.

It also reveals that 22 per cent of men and 20 per cent of women are current smokers, roughly the same as in previous years.

The number of current smokers is highest in London (26 per cent) and the North West (24 per cent), and lowest in the East Midlands and South West (19 per cent).

Among pregnant women trying to quit, 45 per cent are now successful, down from a peak of 53 per cent in 2005-06, the report shows.

However, far more mothers-to-be are now attempting to quit, from 4,000 quit dates and 1,900 successful attempts in 2001-02 to 22,000 quit dates and 9,900 successful attempts in 2010-11.

Information Centre chief executive Tim Straughan said: “NHS Stop Smoking Services in England saw more quit dates set with it in the last financial year than ever before; and indeed the greatest ever number of successful quit attempts.

“But while a bigger number of quit dates are being set with the service and the number of attempts to successfully kick the habit have also risen, overall the success rate is hovering at just below half.”

A spokesman for the Department of Health said smoking was one of the biggest challenges in public health.

“A record number of people have stopped smoking which is a testament to the excellent work of NHS professionals in local stop smoking services.

“The latest figures show that the percentage of adults who smoke has not changed since 2007 and over 80,000 people still die in England each year from smoking-related diseases. So we must go further to reduce smoking rates.

“That’s why in March we published our plans to help drive down smoking rates and reduce the harms from tobacco over the next five years.”