(TNS) -- Portland transportation officials aren't collecting enough data to effectively police the recently deregulated taxi industry, the city's independent auditor found.

In a report released Wednesday, which reviewed the Transportation Bureau's oversight of taxi companies as well as Uber and Lyft, auditors found that most of the city's traditional taxi companies have failed to report required data, such as wait times and ride cancellations, that can help measure the level of service they're providing.

Some companies, the audit found, may underreport the number of rides they provide, potentially dodging thousands of dollars in fees to pay for the regulatory program.

"The Transportation Bureau has focused on monitoring safety," said audit services Director Drummond Kahn, "but now it needs to increase its monitoring of service."

Portland last year removed much of its regulation of the taxi industry, including caps on the number of taxis and fixed prices, at the same time it legalized market newcomers Uber and Lyft.

Portland is among many cities trying to navigate a tectonic shift in its taxi industry. Uber and Lyft together seized 60 percent of the city's ride market within months of their arrival, in part taking market share from traditional taxis but mostly increasing the size of the market. Investors have valued the fast-growing, privately held companies at more than $5 billion for Lyft and more than $60 billion for Uber.

There are some safety issues uncovered in the audit.

For one, the city has collected only crash data from the companies in aggregate, without information that would allow the city to identify problem drivers.

And in its inspections of 600 Uber and Lyft driver, auditors found, 30 were found to be ineligible because of suspended driver's licenses or poor driving history. The audit recommended more targeted inspections based on risk rather than market share. (The Oregonian/OregonLive reported on enforcement data earlier this year and found Uber and Lyft drivers were more likely to run afoul of the city's rules.)

That issue has added relevance because the city has allowed companies to conduct background checks on prospective drivers rather than do its own.

"If the city is relying on businesses to do background checks, it's especially important that those happen correctly," Kahn said.

The primary focus of the audit, however, was that most taxi companies have failed to turn over data on ridership, wait times and wheelchair-accessible service. In approving Uber and Lyft and deregulating the taxi industry, the City Council hoped to improve service in the city and cited those measures in particular.

The ride data is a particular concern because riders pay a 50-cent surcharge, which is intended to fund the cost of inspections and other administration. Companies that underreport their ridership may not be paying their share. The fees are expected to raise cover the cost of regulation, which was $1.4 million in the last fiscal year.

In response to the audit, Transportation Bureau Director Leah Treat said the city's challenge in collecting data from taxi companies stemmed from the technology those companies are using. Uber and Lyft, technology-focused companies used to working with the vast quantities of information they collect, have turned over data much more reliably, the audit said.

"Many of the smaller taxicab companies don't have the technological ability to capture this data," Treat wrote, "and we are providing them technical assistance to help them comply."

The audit also reported on the state of the ride-for-hire market, which has changed dramatically since Uber and Lyft started operating in the city permanently in 2015.

Weekly taxi ride numbers have been fairly steady since then, and cabs were giving about 3,000 rides a day in April 2016. However, the number of taxis and drivers has increased since the City Council removed a cap on taxi licenses at the same time it legalized Uber and Lyft.

Uber and Lyft ridership has climbed dramatically in the same period. The number of rides they provide, however, was not disclosed under the terms of their non-disclosure agreement with the city. Both San Francisco-based companies consider such data to be a trade secret.

The Oregonian/OregonLive has sought those numbers under Oregon's public records law, and the Multnomah County district attorney ordered the city to turn the records over. However, a Multnomah County Circuit Court judge temporarily blocked the release at the request of Uber and Lyft, which are seeking a permanent injunction against the release of the information.

©2016 The Oregonian (Portland, Ore.) Distributed by Tribune Content Agency, LLC.

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