According to Piper Jaffray analyst Gene Munster, “Antennagate” — the problems, or perceived problems, with the antenna on the iPhone 4 — cost Apple 20% of sales — but the lack of a Verizon iPhone is a bigger problem.

“Fortune” ( says those are some of the findings a survey released Wednesday by Piper Jaffray’s Gene Munster. His team interviewed 258 cell phone users in downtown Minneapolis. Munster says:

° 177 respondents, or 69%, indicated that they were aware of iPhone 4 quality issues. Of those who are aware of the antenna issues, 20% indicated that they impacted their purchase decision.

° For every one respondent that acknowledged the antenna issue about three complained about the iPhone not being on Verizon.

° Despite this, Apple continues to sell iPhone 4s faster than it can make them.