Two researchers faced dozens of questions from legislators Monday after a report published last week recommended an increase of up to $2 billion in funding for Kansas schools.

Lori Taylor, a Texas A&M University professor, and Jason Willis, who works with the nonprofit WestEd consulting firm, explained their methodologies for determining how the state can achieve a 95 percent high-school graduation rate.

The state’s 2016-2017 graduation rate was 86.1 percent, according to the study.

Willis said they looked at a range of information, including current student achievement scores, the state’s Every Student Succeeds Act plan, and Kansas’ historical patterns of performance and funding.

Taylor said there was a “strong statistically significant and positive relationship” between student outcomes and expenditures.

The report outlines two scenarios for math and English Language Arts performances. If lawmakers follow either of the two recommendations, annual spending would increase from $4.65 billion for the current school year to $6.44 billion or $6.72 billion in the next five years.

“Clearly, I think everybody can acknowledge that these cost estimates are large,” Willis said.

Senate Majority Leader Jim Denning, R-Overland Park, said the amount of money being asked for schools is “148 percent of 100 percent of the tax growth in Kansas. So just to put that into perspective.”

Willis said various bodies — including the state’s executive branch, Legislature, board of education and the populace — have to decide what is an acceptable level of performance and at what pace.

“When there is consensus and we see evidence of this in other states across those various bodies of government, there seems to be a coalescence around the amount of resources that need to be invested in the system,” he said.

Taylor said the analysis uses data to best predict the level of spending needed for improving performance. It takes into account a number of factors, including student demographics, geographic cost drivers and district size.

She noted that the state’s districts spend efficiently.

“When we looked in Kansas, what we are observing is that the cost efficiency of the Kansas school building is typically quite high — that on average, we’re talking about a cost efficiency of nearly 96 percent, and that is remarkably good. It suggests a very prudent use of resources to produce the outcomes required by the state,” Taylor said.

Willis said a large injection of funding should go through a “phase-in period.” The most important reason for going that route is “for leaders of your schools and districts to take the time to plan how they will use that money,” he said.

The report doesn’t include suggestions on where funds will come from or how it should be spent. The 2017 Legislature approved a $300 million increase in school funding, paid for through a tax hike, but the Kansas Supreme Court ruled the funding was still inadequate.

Allocating resources to achieve improved performance is “overwhelmingly complicated,” Willis said. He said some states have focused on early childhood education, for which Taylor noted it would take time to see the effects.

Rep. Steven Johnson, R-Assaria, and Molly Baumgardner, a Louisburg Republican who chairs the Senate Education Committee, wanted to see additional projections for incremental spending options and graduation rates.