If the government shutdown lasts another two weeks, the total cost to the U.S. economy would exceed the price of building the proposed border wall. According to an estimate by S&P Global Ratings, it will only take another two weeks to cost the economy more than $6 billion, exceeding the $5.7 billion that President Donald Trump demanded to fund his proposed border wall. The U.S. economy will have lost $3.6 billion by Friday, according to S&P. "We estimated that this shutdown could shave approximately $1.2 billion off real GDP in the quarter for each week that part of the government is closed. That may seem like pennies for the world's biggest economy, but it means a lot to those workers trying to cover their household costs without their paychecks," Beth Ann Bovino, S&P's chief U.S. economist, said in a note on Friday.

A demonstrator holds a sign, signifying hundreds of thousands of federal employees who won't be receiving their paychecks as a result of the partial government shutdown, during a "Rally to End the Shutdown" in Washington, January 10, 2019. Carlos Barria | Reuters

The firm came up with these figures by looking at costs related to the shutdown including lost productivity by furloughed workers and a decrease in sales for contractors to the government. The partial government shutdown entered its 21st day Friday, tying the record for longest lapse in federal funding. Lawmakers have failed to fund about a quarter of the government, as President Donald Trump demands money for his proposed border wall. Trump has threatened to veto legislation passed by the Democratic-controlled House to reopen the government temporarily, and that has deterred the GOP-controlled Senate from passing it.

Consumer spending

As the government shutdown nears a record-breaking run, retailers like Best Buy and Bed Bath & Beyond could start to feel the bite from lower consumer spending. With 800,000 federal workers not being paid and a potential delay in tax refunds, the economic effect of the partial government shutdown could be at least $2 billion per week, according to Wells Fargo retail analysts. The retailers that would be hurt the most include those that sell more discretionary goods such as Best Buy and Bed Bath & Beyond and those operating in regions with high government employment, including Ulta Beauty and Dick's Sporting Goods, the bank predicted. Retailers that sell household necessities may have more of a cushion now, but "if the shutdown were to eventually impact benefit programs like SNAP, players like dollar stores, Walmart and Kroger could feel pressure," Wells Fargo's Zachary Fadem said in a note to clients Friday. "On the other hand, history illustrates that prior shutdowns had limited impact on retailers with staples-like characteristics, including grocers and auto part retailers." Wells Fargo is not alone on Wall Street seeing the damage from the shutdown hitting retailers. Jefferies took a closer look at the areas with the most workers affected by the shutdown — Washington, D.C., Maryland and Virginia. Companies including restaurant chain Chuy's, and retailers The Container Store and Nordstrom, that have a higher percentage of locations in those areas will likely experience more damage, Jefferies said. "Impact from the government shutdown could extend well beyond some restaurants in DuPont Circle, "Jefferies' Laurence Alexander said in a note Tuesday, referencing a section of Washington, D.C.

Wall Street cutting GDP forecasts

The shutdown in 2013, which lasted 16 days, shaved 0.4 percent off GDP in the fourth quarter of 2013. Alexander pointed out that payments to government contractors are likely to be affected as well as home sales because of delays in federal loans. J.P. Morgan economists have already cut their first-quarter growth forecast by a quarter point to 2 percent because of the shutdown. Bank of America Merrill Lynch economists shaved 0.1 percentage point from fourth-quarter growth, bringing that forecast to 2.8 percent, due to the shutdown.