Impact bonds and outcomes funds: year-on-year growth (Brookings Institution)


Quick Data Facts

Pay for success securities growth over time

The blue line represents cumulative growth (the number of securities issued since the project began collating the data which is necessarily always increasing.

The green line represents the total number of new PFS securities issued in a year. This value (of course) can be zero or a positive integer.

Brookings Institution

Chart 1: What You’re Looking At

This visualisation shows the growth of impact bonds and outcomes funds as a function of time — since the Brookings project began recording the data in 2010 through to the present.

The purple line shows the cumulative issuance (of impact bonds and outcomes funds) while the green line shows the yearly issuance volume which peaked in 2018 (51).

2018 was the peak year for PFS issuance and while the cumulative graph continues to rise, overall the annual fund activity has been gradually slowing.

Of course, this is precisely the opposite of the trend that we’re hoping to see.


Here’s the same data but in table formula.

You can click the download icon if you’d like to bring it onto your desktop.


About The Data & Brooking’s Pay For Success Tracking Initiative

The data used to create these visualisations was kindly provided by Elyse Painter and Emily Gustafsson-Wright at the Brooking Institution, a think-tank headquartered in Washington D.C.

Elyse and Emily publish a monthly “impact bonds by the numbers” snapshot which charts the growth of social impact bonds (SIBs) and development impact bonds (DIBs) around the world.

Outcomes-based financing: Impact bonds and outcomes funds | Brookings

Since 2014, Brookings has tracked the development of the global impact bond and outcomes funds markets across all sectors, providing updates on the characteristics of contracted deals, as well as analyzing the potential and limitations of these outcome-based financing tools. A particular focus of Brookings impact bonds and outcomes funds research is on education and […]

SIBs and DIBs are the two most popular variants of the “impact bond” — although as the Brookings numbers show, there are far more SIBs in existence than DIBs (the difference lies in whether the ‘outcome payer’ is a domestic government or an international body like a multilateral aid agency).

Their monthly snapshot provides interesting information as to which sectors are most commonly targeted by this pay-for-success mechanism as well as cumulative issuance numbers globally.

For instance, according to their May 2024 snapshot, “social welfare” (79 bonds) remains the leading classification of deployed impact bond (the numbers include both social impact bonds, SIBs, and development impact bonds, DIBs).


The cumulative issuance shows that 2018 was the most prolific year for PFS instrument creation (count: 51). The data authors add that the 2023 total is likely to change as they receive information about projects that haven’t yet been included in the reckoning.

Gustafsson-Wright and Painter note that their reckoning of impact bonds numbers is calculated according to an internal methodology that involves manual verification.

May 2024 Impact Bond Report – Key Numbers

The numbers reflect the cumulative totals for both impact bond variants as of this update (May 2024). According to the figures, the global value of deployed upfront capital in impact bonds currently stands at $517.13M (USD).

ImpactDB