Compiled By Deborah Austin After years of growth from pent-up demand, mobile-phone vendors now face a difficult transition -- illustrated by a 9% decline in third-quarter shipments versus same-quarter 2000 -- says a recent report from Dataquest Inc., a unit of research/advisory firm Gartner Inc., Stamford, Conn. Total third-quarter market fell to 94.4 million units from 103.2 million. Of the top five vendors, three -- Nokia, Ericsson and Siemens -- saw shipment declines. Delays in availability of general packet radio service (GPRS) terminals -- and economic downturns in regions that traditionally enjoyed high mobile-connection growth -- have impacted the industry, say Gartner Dataquest analysts. Shipments in Western Europe, which accounted for about one-third of annual mobile terminal sales in 1999 and 2000, took an unprecedented fall between second-quarter and third-quarter 2001. Nokia remains the market leader with 31.6 million units shipped worldwide, but its aging product portfolio faces more-contemporary competitors, analysts say. Second-place Motorola -- 14.8 million units shipped -- has recorded its third straight quarterly market-share increase and become "a global phenomenon."