Samples of data sources for measuring this outcome:
Graduation rate increases

Data source

County Health Rankings & Roadmaps - high school graduation
County level resources - Under "Explore the Data," select relevant state. Click "Go." Use the "Select a county" drop-down menu.
Kids Count Data Center - graduation rates
State level resources - Select state. Scroll down to "Education indicators." Scroll down to "Other Education." Select "Graduation Rate." (Indicator might not be available depending on the state).