Nine in 10 CTA rides are paid for with Ventra cards, the CTA said today, as the agency moves to eliminate use of Chicago Cards in less than two weeks.

On June 1, riders will no longer be allowed to use their Chicago Cards or load money onto disposable fare cards as the CTA prepares to fully transition to Ventra in July. The agency stopped letting riders reload their Chicago Cards and buy disposable cards on May 1.

In the past two weeks, a few holdouts have switched over to Ventra. Ventra is used to pay for 90 percent of CTA rides, according to data for the week ending May 10.

Before the CTA stopped allowing a reload of Chicago Cards and sale of dispoable cards on May 1, Ventra was used to pay for 86 percent of CTA rides.

The CTA is working to fully transition on July 1, when it will only accept Ventra cards and some banking cards on trains and Ventra, some banking cards, or cash on buses.

Riders who have not yet switched to Ventra may not want to wait until the last minute, because they may encounter lengthier call times than usual.

During the May 1 transition, the Ventra call center experienced a higher-than-usual call volume. From April 28 to 30, the call center saw an average of more than 4,000 calls, compared to a nearly 3,000 call average for the rest of the month, according to an April Ventra performance report the agency posted this week.

On April 30, more than half of the calls to Ventra were placed on hold, which was the highest percentage of April. Average hold time on April 30 was 1 minute, 44 seconds--well below the CTA's five-minute call hold target.

One of the reasons the CTA slowed the transition to Ventra last year was because of lengthy call wait times, a performance standard the CTA said Ventra has been consistently exceeding.

Another reason the CTA didn't fully switch to Ventra last year was because of how long it took Ventra card readers to register a tapped card. The agency is now touting an improvement on bus tap times because of upgrades.

On April 30, average tap times were 0.55 seconds on buses and 0.42 seconds on trains.

At the beginning of April, bus tap times averaged 0.75 seconds. CTA spokeswoman Tammy Chase credited the decrease to Ventra reader upgrades made on buses.

The rail tap time consistently hovered at or below 0.5 seconds for April, according to the report. The agency's goal is to have taps processed in 2.5 seconds or less.