From the link.

>>>With the rising prevalence of cellphones, officials at all levels of law enforcement say cell tracking represents a powerful tool to find suspects, follow leads, identify associates and cull information on a wide range of crimes.

"At every crime scene, there's some type of mobile device," said Peter Modafferi, chief of detectives for the Rockland County district attorney's office in New York, who also works on investigative policies and operations with the International Association of Chiefs of Police. The need for the police to exploit that technology "has grown tremendously, and it's absolutely vital," he said in an interview. <<<

I would think that with hundreds of millions of digital devices in the country 1.3 million requests for taps and data do not seem like much at all.

Say the DEA has a witness to a drug buy. Two people are identified. There would be a "demand" for recording of the calls on each phone, a request to track the two phones' GPS history, possibly a request for phones within a hundred yards of the buy. taps on the phones these phones talked to etc etc. One investigation could spark dozens of requests.