The number of phone numbers searched under the National Security Agency's phone-data surveillance program increased by 50 percent last year, according to a report that otherwise provides scant new information on the numbers of Americans and foreigners subject to U.S. surveillance.

The report, by the Director of National Intelligence, focused on the mechanics of a network of surveillance programs that sweep up millions of American phone records and gain indirect access to 75 percent of the nation's telecom infrastructure to facilitate those searches.

The report, the first such effort under new Obama administration guidelines pledging greater transparency, was as notable for what it left out as what it provided.

For example, the report provides no acknowledgment of the millions of American phone records collected by the NSA to build its database for searches, nor did it provide the number of Americans whose communications get swept up in the process of investigating foreign intelligence targets.

The 50 percent increase in phone numbers searched, for example, represents a relatively small number: 423, up from 288 in 2012. Until Friday, the only recent statistic officials had provided on the program was the 2012 figure.

However, those figures represent the number of terror suspects whose phone numbers are searched daily against continual, new data dumps of American phone records, and any connection can be searched two degrees out from the original phone number to create vastly larger groups of individuals whose records are examined.

The government also for the first time reports the number of known or presumed U.S. persons who were the subjects of data queries in 2013 was 248.

"U.S. person" is a term of art for American citizens and people who are in the country legally.

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