Postcard sales are declining as consumers become more savvy with the technology and are increasingly willing to pay more for postcards than ever before.

But a new study from the University of Michigan suggests that the postcards business is struggling as consumers are increasingly wary of the quality of the paper and how long it takes to deliver.

The study, published Wednesday in the journal Science, analyzed the sales of nearly 2,500 postcards issued by the USPS between 2000 and 2010.

The USPS has a total of more than 17,000 postcards in circulation.

The average size of a postcard is about 1.5 by 1.25 inches.

It’s a tiny size, but it’s about the size of two postage stamps.

The report said the average time to deliver a post card was 4.3 days, which is below the industry average of 6.6 days.

The survey was done by an outside company called PostcardIQ that specializes in measuring customer satisfaction, which can be a key indicator of whether the post cards are actually good quality.

The company is also looking into the quality and speed of delivery.

The Postal Service declined to comment.

The paper is less dense than the traditional postcard and has to be punched and folded before being sent.

It also takes longer to deliver the post card than standard paper mail.

The postcard also has to sit in the mail for a day before being packaged and shipped.

In fact, the average postcard takes about nine months to arrive, according to Postcard IQ.

But USPS says that while the average delivery time was 6.7 days, it’s more like 11 to 13 days for some postcards.

The problem isn’t just about delivery time.

The research found that customers also felt less satisfied when the post office couldn’t guarantee delivery on time.

One respondent said the post service is being forced to give postcards out late because it’s too expensive to keep shipping packages by hand.

Some people said the USPS is too lenient with its delivery time, saying they’re paying more for paper postcards that deliver more quickly.

Postcard buyers have a choice when it comes to the quality postcards they receive.

Consumers can choose to send their postcards by mail or postcard by postcard.

Postcards can be signed by the person receiving them, or they can be scanned using technology to create an image that can be added to the postbox or delivered to the recipient.

If the postmaster is unsure whether a post is a signature, the USPS will send the postman a signature card for that post.

But some postmasters said it’s difficult to ensure signature is present on a post that’s scanned.

There’s also the issue of postage.

Many post offices are offering cheaper postage for postcard deliveries than the more expensive standard postcards for certain products.

The Post Office of Southern California, which has the largest fleet of postcards worldwide, says it uses a higher grade paper called Felt in most of its postcard production.

The price of Felt postcards varies from postcard to postcard, depending on the value of the stamp and the quality it’s made of.

A $100 stamp is worth about $25, and a $100 postcard could be worth $50.