π-core citation rate
The π-core citation rate, or π-rate, is the ratio of the π-core citations divided by the number of publications in the π-core. It is simply the average number of citations per core publication.
$$\pi\text{-rate}=\frac{C^\pi}{P_\pi}=\frac{\sum\limits_{i=1}^{P_\pi}C_i}{P_\pi}=\frac{100\pi_\text{index}}{\mathrm{floor}\left(\sqrt{P}\right)}$$History
| Year | π-rate |
|---|---|
| 1997 | 1.0000 |
| 1998 | 5.0000 |
| 1999 | 12.3333 |
| 2000 | 20.0000 |
| 2001 | 28.0000 |
| 2002 | 43.0000 |
| 2003 | 54.4000 |
| 2004 | 76.2000 |
| 2005 | 110.6000 |
| 2006 | 142.5000 |
| 2007 | 186.1667 |
| 2008 | 224.8333 |
| 2009 | 265.1667 |
| 2010 | 291.5714 |
| 2011 | 330.4286 |
| 2012 | 377.1429 |
| 2013 | 419.5714 |
| 2014 | 445.6250 |
| 2015 | 491.8750 |
| 2016 | 543.3750 |
| 2017 | 589.5000 |
| 2018 | 635.5000 |
| 2019 | 679.7500 |
| 2020 | 724.8750 |
| 2021 | 768.1250 |
| 2022 | 776.2222 |
| 2023 | 817.2222 |
| 2024 | 859.6667 |
| 2025 | 879.5556 |