Data Envelopment Analysis of Government Subsidy Efficiency in New Energy Vehicle Enterprises: A Semi-Parametric Approach

• • Average technical efficiency of NEV enterprises is 0.743, with pure technical efficiency rising to 0.812 after environmental adjustments, indicating that external factors account for ~9% efficiency variation. • • Optimal government subsidy intensity is ~15,000 RMB per vehicle; subsidies beyond this threshold reduce efficiency by 0.05 per 1,000 RMB increase, highlighting diminishing returns. • • Scale efficiency averages 0.89, with 60% of enterprises operating at decreasing returns to scale, suggesting consolidation opportunities to achieve optimal scale. • • Regional analysis shows eastern enterprises outperform central/western by 12% in efficiency, driven by charging infrastructure density (per 100 km²) and R&D expenditure share (≥5% of revenue).