Crowds packed subway platforms and trains in Union Square as cold weather wreaked havoc on a Monday morning commute. View Full Caption DNAinfo/Trevor Kapp

UPPER EAST SIDE — When signal problems delayed the 4 train and made Tammy Prather late for work earlier this year, the claims analyst from Brooklyn took to Twitter to yell at the Metropolitan Transportation Authority.

No matter what time I leave for work, I end up delayed. Thanks @MTA @NYCTSubway — Tammy (@bishboobye) February 4, 2015

It didn't take long for NYC Transit's Twitter account to respond. "Sorry you were delayed. You can fill out a delay verification form to give to your boss."

Prather, like one of 22,300 4 train riders in 2014, requested what is known as a subway delay verification.

In total, the MTA issued almost 129,000 delay verifications to riders last year, up 40.6 percent from the almost 92,000 offered in 2013 and a fourfold increase from the 31,000 delay verifications issued in 2010, when the program launched.

The MTA verified 97 percent of the delay verifications passengers requested in 2014.

So far this year, the MTA has received almost 109,000 subway delay verification requests, according to data obtained by DNAinfo New York through a Freedom of Information Law request.

"I try to check the MTA's site before I leave to make sure there's no delays but it's always packed and there's usually a delay or a signal problem," said Prather, 29, who catches the 4 at Utica Avenue in Brooklyn on her way to work in Flatiron. "You don't know what a signal problem is or why it's an issue. It's hopeless."

Riders on the the overcrowded 4, 5 and 6 lines on the East side requested more than 54,420 combined excuse notes from the MTA in 2014, according to MTA data. That's more than the lines ranked sixth through 10th combined.

The 4, 5, and 6 lines are also in the top five for delayed trains in 2014 with between 29 and 33 percent of trains on the lines arriving late.

MTA spokesman Kevin Ortiz said the 4, 5 and 6 Lexington Avenue line is the busiest in the system with an average of 1.95 million riders per day.

"Once phase one of the Second Avenue subway is done, that will shift 220,000 of those customers over," Ortiz said.

Rounding out the top five are the A line with 19,450 excuse notes requested by riders and the 2 line with almost 16,000 requests.

Mike Farmer, 26, a project manager for Barbizon Lighting, said his commute from Washington Heights to Columbus Circle on the A should be better, especially since the A train is express.

On June 22, the southbound A train was delayed even though he says there was no notification on the MTA's website.

@MTA trying to get me fired? Extreme delays on SB A train and no 'delays' notice on website? How can I prove it? #MTA #gladmybossgetsit — Mike Farmer (@FarmerMLights) June 22, 2015

"I check the website before I leave the house and a lot of time they don't put up that something is going on. Somewhere between 168th Street and 145th Street we stop moving," Farmer said.

"I understand the system is huge and it is old but a lot of their customers have no other means of transportation. We would just appreciate better communication."

February saw the highest number of subway delay verification requests with 15,867 notes. Ortiz said that was due to the number of snowstorms that month and the havoc it wrought on subway equipment.

The worst day was Feb. 5, when a power failure forced the suspension of services along portions of the 1, 2, and 3 lines. The 2,450 riders who requested a subway delay verification note that day reported an average delay of 53.4 minutes.

"It was snow and other events related to snow such as an arching insulator, a spark that can cause a fire when salt hits the third rail," Ortiz said.

Jan. 15 was another terrible day for delays after a water main burst in Greenwich Village. More than 1,900 riders requested a subway delay verification for delays that averaged 32 minutes.

The G and the Z lines had the fewest number of excuse-note requests among the non-shuttle lines. In 2014, 2,739 delay verification notes were requested from G train riders and 463 requested from Z train riders. Both lines have between 125,000 and 200,000 daily riders.

John Raskin, executive director of the Riders Alliance, said the number of subway riders needing excuse notes can be expected given the record ridership and the MTA's aging infrastructure.

"Crowding can be a factor in train delays and breakdowns. With record subway ridership there is no room for error," said Raskin. "If one train has a mechanical problem that causes a ripple effect that makes literally thousands of people late for work."

The only way to address the problem is to invest capital funds to upgrade the system, the MTA said. It just approved a $29 billion capital plan that devotes hundreds of millions to new cars, infrastructure repairs and a communications system that allows the trains to run closer together.

The announcement came after a months-long fight between Mayor Bill de Blasio and Gov. Andrew Cuomo over how to fund the capital plan.

The city upped its contribution to $2.5 billion, the most it has ever contributed, and the state committed $8.3 billion. But by 2020, only 68 percent of stations will have countdown clocks that display the arrival time of trains due to cuts in the anticipated capital plan.

Politicians, advocacy groups and residents are still fighting the proposed MTA plan to cut $1 billion from the project to build the second phase of the Second Avenue subway, stretching north to 125th Street.

Following the outcry, MTA Chairman Thomas Prendergast said last week that the MTA will pursue a capital budget amendment to speed up the second phase of the Second Avenue subway if possible.

"Many of these problems can't be fixed without billions of dollars in capital investment," said Raskin. "The capital plan is a step towards solving all of this but what we are investing does not match the magnitude of what public transportation needs."

That angers riders like Farmer, who followed the back and forth over MTA funding.

"Why in this transportation system that is so large and relied on by so many is it so hard to get the funding needed to keep it going?" asked Farmer. "It really is the main artery of the city."

Until things get better, Prather said she will continue to use the delay verifications. She says she's requested five in the past few months alone and has been trying to leave home even earlier.

"The notes are useful if you have a boss that needs to see the proof," Prather said, "but I would rather not be delayed."