Eircell has classified about 63,000 customers or 4 per cent of its customer base as "inactive users" in figures published by its parent company, Vodafone.

According to figures released yesterday, just over 1.5 million customers made calls on the Eircell network within a three-month reporting period to June 30th. These are the first subscriber figures which show Eircell's active user base following the introduction of a new policy by firms to more accurately reflect mobile use.

Although "inactive users" will remain on Eircell's subscriber base, they will not be treated as active users unless they make a call within a three-month period.

Analysts had expressed concerns that mobile firms may have been exaggerating their market share by including customers who may have gone to other networks.

Earlier this month, British Telecom figures showed Esat Digifone had struck off 100,000 users this year, some 10 per cent of its active customer base.

Digifone reported that it had 997,000 users in the period to June 30th.

The combined active customer base of Digifone and Eircell now totals some 2.5 million users. Some 71 per cent of Eircell's user base owns a pre-paid mobile phone.

Vodafone shares fell 2.5 percent to 144-1/2 pence sterling in late trade yesterday. However, Vodafone said there were signs of stabilisation in average revenue per user over the past six months.

An Eircell spokeswoman said revenue figures for the Irish subsidiary would be published in Vodafone's annual results in the early autumn.