FTSE 100 directors saw a median pay rise by 14% over the past year, largely boosted by long-term incentive plans (LTIPs) according to research by Income Data Services (IDS).

Analysis from the annual IDS Directors' Pay Report shows that although salary increases at the biggest listed companies were modest, and annual bonuses fell, a 58% rise in the median value of vested LTIPs saw total earnings increase significantly.

Many directors were allocated a large block of shares three years ago when equity prices were low. Share prices have subsequently risen, bringing windfall gains.

Steve Tatton, the report's editor, said: 'With nearly two-thirds of FTSE directors benefiting from an LTIP award in the latest year, the higher share-based payouts clearly made up for any ground lost in lower annual bonuses.'

IDS said FTSE 100 directors' salaries increased by a median of 4%, while the value of bonus payment fell 8.8%. In contrast, the median value of LTIPs grew 58%. The median salary was £568,500, annual bonus £553,200 and vested LTIP awards £1.2bn.

Tatton suggested that changes to financial reporting which now require companies to provide a single total pay figure for senior executives may turn the spotlight on the role of LTIP in boosting salary packages.

'By putting the transparency of these schemes at the heart of new reporting requirements, the government is likely to ensure that LTIP schemes are the subject of much tougher questioning by shareholders in the future,' Tatton said.