Each year, we share the number of R01-equivalent* and R21 applications that NIAID received in the previous fiscal year (FY) as well as the number of grants NIAID awarded. To add context, we present the data alongside the same figures for the preceding 4 years.
The COVID-19 pandemic impacted NIAID’s extramural funding patterns, interrupting what had been steady trendlines of application and award counts from FY 2013 through FY 2019. Having passed through several years of tumult, any new assessment of long-term trends will need to account for fluctuations during the pandemic. It’s hard to make projections at this point in time.
Coincidently, NIH’s Office of Extramural Research recently published FY 2023 By the Numbers: Extramural Grant Investments in Research, which presents relevant NIH-wide data. We make references to that reporting below as well.
Application Counts
| FY 2019 | FY 2020 | FY 2021 | FY 2022 | FY 2023 | |
| R01-Equivalent | 3,225 | 3,503 | 3,981 | 3,473 | 3,609 |
| R21 | 2,530 | 2,728 | 4,152 | 2,845 | 2,505 |
In FY 2023, the number of R01-equivalent applications increased by 3.9 percent from FY 2022 and increased by 1.8 percent in comparison to the average of the previous 4 fiscal years. From FY 2004 to FY 2018, the count of R01-equivalent applications vacillated between approximately 2,450 and 2,900; FY 2019 was the first time the total surpassed 3,000 and the tally has since remained well above that threshold.
Compared to the FY 2022 total, the number of R21 applications decreased by 12.0 percent in FY 2023 and decreased by 18.2 percent compared to the average of the previous 4 fiscal years. The high R21 application count in FY 2021 appears to have been an outlier. The gap between R01 and R21 application counts is greater now than it has been in any year since FY 2010.
Across NIH, Research Project Grant applications decreased by 4.9 percent from FY 2022 to FY 2023, and, within that category, R01-equivalent grant applications dropped by 3.1 percent over the same period.
Next, consider our paylines for R01 and R21 grant applications over the last 5 years. Remember that the R01 paylines are calculated as percentiles while the R21 paylines are determined using overall impact scores, as explained at Understand Paylines and Percentiles.
Paylines
| FY 2019 | FY 2020 | FY 2021 | FY 2022 | FY 2023 | |
| R01 | 14 | 14 | 14 | 12 | 12 |
| R21 | 31 | 31 | 31 | 28 | 29 |
The R01 payline was flat in FY 2023 as compared to the prior fiscal year, while the R21 payline increased slightly versus FY 2022. For both activity codes, FY 2023’s paylines are below the level our paylines held from FY 2019 to FY 2021.
That plateau—an R01 payline set at 14 in FY 2019 through FY 2021—represented our R01 payline’s highest point since FY 2007. The R21 payline of 31 in that same time frame was 1 point below the FY 2018 payline of 32, which was the high point for our R21 payline over the past 13 years.
Keep in mind, the R01 paylines listed above are for established investigators. NIAID sets a separate payline for new and early-stage investigators, usually four percentiles higher than the R01 payline for established investigators.
Given those yearly paylines, NIAID funded the following numbers of awards:
Award Counts
| FY 2019 | FY 2020 | FY 2021 | FY 2022 | FY 2023 | |
| R01-Equivalent | 665 | 802 | 636 | 575 | 628 |
| R21 | 530 | 619 | 662 | 401 | 533 |
On a positive note, the count of competing R01-equivalent awards in FY 2023 increased by 9.2 percent compared to FY 2022, and the number of R21 awards in FY 2023 increased by 32.9 percent compared to FY 2022. Within the table above, FY 2022 stands out as a down-year for competing awards. In comparison to the average of the previous 4 years, the count of competing R01-equivalent awards in FY 2023 amounts to a decrease of 6.2 percent and the number of R21 awards in FY 2023 is a decrease of 3.6 percent.
To be clear, the figures in the preceding table are for newly made competing awards, not all active awards. Most of the R01-equivalent competing awards made in FY 2019 through FY 2022 remained active in FY 2023. So, despite varying numbers of new research project grants year-by-year, NIAID’s overall commitment to research project grants increases nearly every year, as seen at Research Project Grants: Funding, by Institute/Center (click on the “NIAID” column to filter for our Institute).
Across NIH, the number of new research project grant applications decreased by 2.3 percent from FY 2022 to FY 2023, and for R01-equivalent awards, specifically, the number of new awards decreased by 2.9 percent.
It’s worth noting that the average size of R01-equivalent awards has steadily increased over time; refer to R01-Equivalent Grants: Average Size. NIH-wide, the average amount of support for a new R01-equivalent award increased by 2.7 percent from FY 2022 to FY 2023. Given a flat budget set against an inflationary backdrop, each R01-equivalent award needing more support could limit our capacity to make as many R01 awards.
The tables above combined to yield the following success rates:
Success Rates (in percentage)
| FY 2019 | FY 2020 | FY 2021 | FY 2022 | FY 2023 | |
| R01-Equivalent | 20.6 | 22.9 | 16.0 | 16.6 | 17.4 |
| R21 | 21.0 | 22.7 | 15.9 | 14.1 | 21.3 |
NIAID made more R01-equivalent awards in FY 2023, so that even with an increase of incoming applications, the success rate for applicants was about 1 percentage point higher than FY 2022. Still, the success rate for R01-equivalent awards has not yet returned to levels typical before the pandemic.
For R21 award applications, FY 2023’s success rate was remarkably higher than that of FY 2022—more than 7 percentage points. The success rate in FY 2023 matched that of FY 2019. An increased R21 award count combined with a lower application volume significantly drove up the success rate.
We often hear potential applicants speculate that an R21 award is easier to get, and while the success rate for R21 awards jumped in FY 2023, recent success rates for the two activity codes don’t necessarily validate that claim. If you’re deciding which activity code to use for an investigator-initiated application, the size and scope of your project (e.g., cost and time requirements), rather than presumed success rates, should determine which mechanism you use—see Comparing Popular Research Project Grants—R01, R03, and R21.
This Year
Looking ahead, the FY 2024 interim R01 payline for established investigators is currently set at the 8 percentile. The FY 2024 interim R21 payline is set at an overall impact score of 23.
Most years, our final paylines are higher than the interim paylines we set at the start of the fiscal year. Currently, we are operating under a continuing resolution, so our paylines are set conservatively. For more on our budget process, read NIAID Paylines and Budget Information Changes Throughout the Year.
Remember, success rates are the quotient of dividing an award count by the corresponding reviewed application count. We don’t yet know how many applications NIAID will receive in FY 2024. Nor do we know what NIAID’s overall appropriation will be (i.e., award count). That said, we aim to maintain success rates for R01-equivalent and R21 applications that are as high as possible, and we organized our Financial Management Plan to give us the best possible chance of achieving good success rates.
*In this article, “R01-equivalent” combines the R01 and Method to Extend Research in Time Award (R37) activity codes. Note that, in other contexts, NIAID and others may include additional activity codes when tabulating “R01-equivalent.”