A science policy analyst is evaluating the impact of research grants. If a grant of $50,000 increases a lab's output by 20%, and a second grant of $30,000 increases output by an additional 15%, by what percentage does the total grant increase the lab's output? - Sourci

Understanding the Context

Imagine a laboratory receiving two separate funding injections: a $50,000 grant and a subsequent $30,000 grant. According to recent analysis, the $50,000 grant increases lab output by 20%. Then, the additional $30,000 grants a further 15% increase. The core question is: by what percentage do the combined grants boost total output?

Step-by-Step: Calculating the Cumulative Growth

To evaluate the total effect, analysts use the principle of sequential percentage increases. However, because percentage gains are applied to an evolving baseline (not the original grant amount), we must compute the compounded output change:

1. First grant (-$50,000):
   Output increases by 20% → New output = 100% + 20% = 120% of original

Key Insights

2. Second grant (-$30,000):
   The $30,000 increases output by an additional 15%—but of the already increased amount:
   15% of 120% = 0.15 × 120% = 18%
   New output = 120% + 18% = 138% of original

Thus, the total increase from baseline (100%) is 38%, but the question asks for the percentage increase in output resulting from the grants, relative to the original output.

Percentage Increase from Combined Funding

The total grant is $50,000 + $30,000 = $80,000, but output growth stems not from total spending, but from how each grant uplifts productivity. The output reaches 138% of original due to the sequential improvements.

Therefore, the total output increase due to grants is:

Final Thoughts

138% (final) – 100% (original) = 38% increase

However, analysts often report not just absolute output changes, but the marginal impact of each funding tier. The 20% rise from $50,000 reflects strong upfront productivity gains, while the 15% uplift from $30,000 indicates diminishing returns or diminishing marginal returns in funding efficiency—common in scaled research environments.

Policy Implications

Understanding this dynamic helps science policymakers:

• Allocate funds strategically: Larger grants may not always yield proportionally higher output; optimization between multiple smaller grants versus one large one matters.
  
• Assess ROI: A $50k grant delivering 20% output growth suggests strong early-stage productivity, while smaller, follow-up grants contribute diminishing but meaningful gains.
  
• Improve grant design: Funding models that preserve incentive structures across tiers optimize lab performance.

Conclusion