DESPITE HIS SUCCESS AT TURNING AROUND BOLTON, Sam Allardyce was sacked by Newcastle United after 24 matches in charge this season following some poor results.

That, at least, might be a cynical interpretation. But 16 months has become the average tenure of a sacked Premier League manager. And that time-span is getting shorter.

Hence apocalyptic warnings that all clubs will become like Leicester City, who had five managers, plus a pair of caretakers, last year.

And coaches like Francesco Guidolin, now in his third spell in charge of Palermo, or even the entire league like the Brazilian, where bosses are routinely fired and, in some cases, re-hired.

Yet, of the seven sackings in the Premier League this season - Steve Bruce, who lasted the best part of six years at Birmingham, counts as a resignation - the three who had celebrated their first anniversary at a club could all be described as achievers.

Jose Mourinho twice won the Premier League and won four major trophies, Martin Jol took Tottenham to back-to-back fifth-place finishes and Billy Davies secured Derby an improbable promotion.

Chris Hutchings (13 games), Sammy Lee (14), Lawrie Sanchez and Sam Allardyce (both 24) will never know what an entire season at the helm would have brought.

They are not alone. Research done at Warwick University, where the Pro-Licence managerial qualification is run by the academic Dr Susan Bridgewater on behalf of the League Managers' Association (LMA), shows that top management is an increasingly precarious profession.

In 1992/93, the first season of the Premier League, 30 Premier League or lower-division managers were dismissed. But they had enjoyed an average of 3.12 years at their club.

Fast forward to 2007/08 and that figure, across all four divisions, is at an all-time low of 1.38 years, reflected by the 16 months the average axed top-flight managers mustered.

The figure of seven sackings is the highest at this stage of the season. It is only topped by the 2001/02 campaign, where there were 10 dismissals, though it should be pointed out that the LMA's figures include post-season sackings.

But it is no coincidence that 2001/02 - when the eventual tally among the 92 Premier and Football League clubs was 10 resignations and 53 sackings - and 2007/08 have brought the most changes.

Television money - or the lack of it - causes football's fault lines to shift, and managers are the casualties.

The current campaign has marked the start of the most lucrative television deal in the Premier League's history, but one consequence is that the cost of dropping out of the division is greater. Hence a change at the top for five of the seven bottom teams.

And 2001/02 marked the collapse of the ITV Digital deal that had promised to make the Football League clubs wealthier.

Suddenly paupers, their reactions often involved the sack. Sometimes it was understandable, with Watford axing the costly Gianluca Vialli to bring in the lower-budget Ray Lewington.

And the financial problems in the lower divisions provoked panic at the foot of the Premier League.

Derby and Leicester, both eventually relegated, changed manager twice within 12 months. It did not do either much good.

Indeed, with the prize of promotion to the Premier League available, the Championship has long been a particularly unstable environment for managers.

An average tenure of 15 months per manager - though it is obviously lower at Leicester - predated the current spate of sackings in the top flight.

Watford's Adrian Boothroyd is now the longest-serving manager in the division, and he was appointed only in March 2005.

The Premier League's veteran predates him by almost two decades.

Alex Ferguson, who moved to Old Trafford in November 1986, and Arsene Wenger, at Arsenal since September 1996, prove what the LMA's chief executive Richard Bevan meant when he said: 'If a club has managerial stability, it is far more likely to be successful.'

But stability appears to be anathema to football clubs now.

stsports@sph.com.sg

Unstable job

1992/93: 3.12

1993/94: 2.30

1994/95: 2.55

1995/96: 2.33

1996/97: 2.42

1997/98: 1.81

1998/99: 1.68

1999/00: 2.04

2000/01: 2.13

2001/02: 2.04

2002/03: 2.02

2003/04: 2.08

2004/05: 2.23

2005/06: 1.84

2006/07: 1.89

2007/08 to date: 1.38

Overall average: 2.19