Whereas the average daily cost of the stoppages by signal staff was estimated at pounds 8m a day, 24-hour strikes by Aslef, the train drivers' union, will each lose British Rail around pounds 10m.
Senior officials said that the business was still struggling to recover from last year's action. They estimated that 2 per cent of passengers were lost to the business permanently.
While passenger revenue in London and the South-East resumed its growth within months of the end of the dispute, elsewhere the picture is worse. The post-recession growth in revenue in the provinces is now around 3 per cent - less than half the previous level.
While long term confidence in the industry's freight business was undermined last year, there was little loss of income because services were rescheduled. British Rail's goods companies are likely to use the same tactic this time round.
Last year, signal box supervisors and managers were pressed into service and some trains ran on most routes. This year, however, there is a strict limit on the number of former drivers who can be draughted in - there are only around 200 staff in managerial grades capable of driving trains and all would need refresher courses.
The four months of signal strikes last year led to a loss to the industry of pounds 173m. At the height of the action last August, passenger revenue stood at pounds 135m compared with pounds 166m the previous year.
In December, after the stoppages were at an end, revenue rose to pounds 181m compared with pounds 170m in the same period of 1993. British Rail calculates that it has taken around two years to recover fully from prolonged disruption in the past.
Also, pounds 140m of British Rail's loss last year was cancelled out by compensation from Railtrack, who refunded charges for the use of track. This time British Rail will bear the full cost.
Stephen Alanbritis, of the Federation of Small Businesses, said his members were "gasping in disbelief" that the strikes were going ahead. He said more than 800 small firms were going broke each week and a prolonged strike could see the toll rise to 1,000, the level at the height of the recession.Reuse content