Are Senators Struggling to Legislate?

Craig Volden and Alan Wiseman write at the Washington Post:

"Republican senators are struggling with how to repeal and replace the Affordable Care Act. Is it just a tough issue — or does the Senate no longer have effective lawmakers?
Our new data analysis suggests that senators’ success in moving bills through the legislative process has declined markedly over the past several decades — undermining the Senate’s capacity to resolve public problems...."

Read more at https://www.washingtonpost.com/news/monkey-cage/wp/2017/06/29/senators-used-to-excel-at-lawmaking-now-not-so-much-heres-what-needs-to-change/?utm_term=.5f9a0879fe62