* Country: Turf field prevalence differs dramatically across countries due to cost, climate, and local regulations. Developed nations with more funding will have higher adoption rates.
* School level: High schools and colleges are more likely to have turf than elementary schools.
* Definition of "turf": The term itself can be ambiguous. Does it include all synthetic surfaces or just specific types?
To find an estimate for a specific region, you would need to research individual school districts or state/provincial education departments. Even then, data may be incomplete or inconsistently collected.