The Every Student Succeeds Act (ESSA) requires states to identify schools with struggling students for comprehensive, additional targeted, or targeted support and improvement (CSI, ATS, or TSI respectively). States must identify schools for CSI when the whole school is among the bottom 5 percent of Title I schools in the state. Meanwhile, they must identify for ATS those schools in which a subgroup of students, on its own, performs as poorly as schools identified for CSI. The chart in the factsheet describes the TSI and ATS definitions for the nine states and Puerto Rico and the likely result of their approach to "screening" ATS schools, according to the key below. Unless otherwise noted, states identify TSI schools annually and ATS schools once every three years, beginning in School Year (SY) 2018-19.