The rampant demand for mobile phones seen in the UK throughout 1999 continued during the first quarter of 2000. Some 3.25 million new customers were added to the four mobile networks in the January-March quarter, to take the total UK customer base up to more than 27 million, almost double the 14 million users at the start of 1999. Orange PLC was the strongest performer in the first quarter, while analysts said BT Cellnet put in a relatively weak effort. "The boom continues," says Sean Johnson, telecoms analyst for SG Securities, London. "It's a solid set of numbers, especially [because] after the record fourth quarter, there was expected to be more of a slowdown." The four UK providers and their number of subscribers are Vodafone AirTouch PLC, 8.8 million; BT Cellnet, 7.4 million; Orange, 5.8 million; and One 2 One, 5 million. The first-quarter numbers are down from the addition of the record 4.4 million subscribers during the fourth quarter of 1999, which was expected due to the buying of phones as Christmas presents. But the upward trend was spectacular throughout 1999 and clearly shows little sign of slowing.