Apple has the highest score ever recorded in the American Customer Satisfaction Index. The company now ranks first in customer satisfaction among PC manufacturers for the fifth year in a row, being followed by runner-up Dell, the only computer company (besides Apple) to record an increase in ranking over their 2007 scores, in the University of Michigan survey.

Claes Fornell, a professor at the university and head of the ACSI, said, "We have never seen a gap between the leader and the rest of the pack this big". However, Apple's lead is likely to have been affected by widespread disappointment with Microsoft's Vista among HP-Compaq, Dell and Gateway customers, 9to5mac reveals.

ACSI reports scores on a 0-100 scale at the national level and produces indexes for ten economic sectors, 43 industries (including e-commerce and e-business) and more than 200 companies and federal or local government agencies. ACSI produces scores for the causes and consequences of customer satisfaction as well as their relationships, in addition to the company-level satisfaction scores. The measured companies, industries, and sectors are broadly representative of the U.S. economy serving American households.

But how is the ACSI data collected? According to the organization's web site, customers of all companies (and some federal agency customer segments) are selected from national and regional probability samples by screening a randomly chosen adult (age 18 to 84 for private sector companies) in each telephone household. Respondents are asked questions about the purchase and use of specific products and services purchased within specified, recent time periods. ACSI notes that these periods vary according to the product or service.

Ultimately, those who qualify as respondents are then asked from which company or which brand they have purchased and responses to the ACSI survey questions are coded as a customer interview for that company. The ASCI is based for each company surveyed on a sample of 250 customer interviews with more than 65,000 interviews conducted annually.