Ever heard the one about infrastructure week?

As politicians make calls to rectify the decline of U.S. infrastructure investment, a new study from Leah Brooks of George Washington University and Zachary of Liscow of Yale University provides "suggestive evidence" as to how and why infrastructure costs could have changed over time.

After digitizing annual state-level data on interstate highway construction — one of the largest projects in American history — they found that per-mile construction costs increased dramatically over time, tripling between the early 1960s and the 1980s. But why?

Brooks and Liscow ruled out some old theories such as the idea that highway planners procrastinated and left the most geographically challenging routes for last, or that costs for labor and materials changed. Instead, one possible explanation they found is that as incomes and home values rose, so did demand for more expensive interstates. For example, the doubling in real median per capita income between the '60s and '80s accounts for about half the increase in construction costs per mile. States were also building more bridges and ramps as incomes increased. The study suggests all this could have occurred simply because the more money people had, the more willing they were to spend it.

One other factor that the study finds consistent with the data is the rise of the "citizen voice" in the late '60s and early '70s. That includes the growth of environmental activism, the civil rights movement, and homeowners organizing as lobbyists. Basically, more power to the people possibly meant more expensive highway construction. The timing checks out, at least.

The findings, the paper says, are suggestive, but not causal. Still, it looks like a good start in bettering our understanding of infrastructure investment over time. Read the full study here. Tim O'Donnell

The Supreme Court said Friday that Justice Ruth Bader Ginsburg has finished three weeks of radiation treatment for a malignant tumor on her pancreas, which was discovered during a July blood test, The Washington Post reports. "The tumor was treated definitively and there is no evidence of disease elsewhere in the body," the court said, adding that "no further treatment is needed at this time." Ginsburg was treated at the Memorial Sloan Kettering Cancer Center in New York.

This is Ginsburg's latest cancer bout after being treated for lung cancer last December; she subsequently worked from home and returned to the court within two months. She was also treated for pancreatic cancer in 2009, as well as for colon cancer in 1999.

According to the statement released on Friday, Ginsburg maintained "an active schedule" amid her treatment, aside from canceling a summer trip to Santa Fe. NPR reports that she continued work and has not canceled any of the 11 events she has scheduled for September. In an interview with NPR published not long before this latest treatment began, Ginsburg opened up about her health, saying, "There was a senator, I think it was after my pancreatic cancer, who announced with great glee that I was going to be dead within six months. That senator, whose name I have forgotten, is now himself dead, and I am very much alive." Brendan Morrow

Good Morning America's Lara Spencer has apologized after coming under fire for seemingly mocking Prince George for his interest in ballet.

During a Thursday segment, Spencer reported on the prince's "demanding" curriculum, noting that it includes not only "the usual" courses but also things like "religious studies" and "ballet." When Spencer got to "ballet" at the end of her list of activities, George Stephanopoulos and others in the room immediately broke out into laughter. Spencer played into their amusement by joking in response to a photo of the prince, "He looks so happy about the ballet class!" She concluded the segment by saying, "Prince William says George absolutely loves ballet. I have news for you Prince William: We'll see how long that lasts."

Spencer is now apologizing, captioning an unrelated Instagram photo on Friday with, "My sincere apologies for an insensitive comment I made in pop news yesterday." She added, "From ballet to anything one wants to explore in life, I say GO FOR IT [because] I believe we should all be free to pursue our passions."

Spencer might have intended to emphasize George's surprisingly busy schedule with her comment, seeing as she noted while wrapping up the segment that he "might end up" just wanting to "go back to the Play-Doh." Clearly, that's not how it came across to viewers, though; the video received more than 1,000 thumbs down on YouTube and went viral. A since-deleted Twitter clip drew strong reactions on Friday, with New York magazine's Olivia Nuzzi writing, "This is so out of touch it's like from another dimension."

Luckily, Prince George can breathe a sigh of relief knowing he now has Good Morning America's permission to pursue his interests. Brendan Morrow

President Trump's wild morning tweets have left Fox News' Chris Wallace fairly baffled.

Wallace appeared on America's Newsroom shortly after the president not only questioned whether the Federal Reserve chair he appointed was an "enemy" of the United States but also claimed American companies "are hereby ordered" to find an "alternative to China." The latter tweet was read to Wallace for the first time live on-air by host Sandra Smith, who — in a vast understatement — informed Wallace that Trump "had moved on to more tweets." Wallace then tried, and mostly failed, to make sense of the "order" issued by Trump.

"The best I can tell, the American president can't order U.S. companies how they're going to do their sales ... we have a free market, capitalist system," Wallace said, suggesting that "most people in this country wouldn't want to see a president be able to" control sales in such a way either.

Wallace then pivoted back to Trump's earlier tweet that suggested Powell is an enemy of the country, reminding viewers that the alleged antagonist "was appointed by President Trump" himself.

"When you have the president of the United States sort of flailing around this way ... is that going to create more consumer confidence about the state of the economy or not?" Wallace rhetorically asked. Perhaps to push viewers toward the answer, Smith immediately noted that the Dow Jones Industrial Average had taken a plunge amid "the president's tweeting."

Wallace concluded the segment by dryly noting that Trump "clearly isn't responding well" to China announcing retaliatory tariffs and suggested we might be in for a "bumpy" G-7 summit this weekend if his tirade keeps up.

"Hold on to your hats," Wallace suggested. Brendan Morrow

In response to new tariffs from China, President Trump is making some demands of American companies.

After China announced Friday that it would be hitting the U.S. with tariffs on $75 billion worth of goods next month, Trump tweeted that "our great American companies are hereby ordered to immediately start looking for an alternative to China." The president is also demanding that business owners "bring ... companies HOME" and make products in the U.S., declaring the situation to actually be "a GREAT opportunity for the United States."

Trump's demand is seemingly more of a strongly-worded suggestion, with The Washington Post's Josh Dawsey noting, "What authority does the president have to order companies to do things?" If Trump has an answer to that question, he might attempt to provide it in a few hours, as he also promises in his tweets that he "will be responding to China's tariffs this afternoon."

The president's initial reaction following the news of China's retaliatory tariffs was to wonder aloud whether Chinese President Xi Jinping or Federal Reserve Chair Jerome Powell was the "bigger enemy" to the United States. The Dow Jones Industrial Average fell more than 400 points amid his tweets. Brendan Morrow

As the U.S.-China trade war continues to escalate, so too are President Trump's attacks on ... his own Federal Reserve chair.

On Friday morning, Trump yet again lashed out at Fed Chair Jerome Powell, angrily tweeting that the "very weak" Federal Reserve "did NOTHING" after Powell failed to reassure that interest rate cuts were on the horizon during the central bank's annual Jackson Hole, Wyoming, symposium.

Trump's attack also came amid mounting fears of a possible U.S recession and China's announcement that it will hit the U.S. with retaliatory tariffs on $75 billion in goods. But Trump went even further than he usually does, this time wondering aloud, "who is our bigger enemy, Jay Powell or Chairman Xi?"

Despite Xi being the head of the country the U.S. is locked in a trade war with and has labeled a currency manipulator, it sounds like Trump was asking rhetorically:

Powell had emphasized Friday that "monetary policy ... cannot provide a settled rulebook for international trade," The Hill reports. Trump has continuously slammed Powell and demanded he lower interest rates, with The Washington Post reporting that he has considered rotating Federal Reserve governors in an attempt to limit Powell's power. The president has also repeatedly insisted that he could fire Powell.

All this marks quite the change in tone from when Trump praised Powell as "strong," "committed," and "smart" in his glowing 2017 Rose Garden ceremony.