%0 Journal Article %T Public debt in the 21st century %T Analyzing public debt dynamics with Debtwatch %+ Observatoire français des conjonctures économiques (Sciences Po) (OFCE) %A Timbeau, Xavier %A Aurissergues, Elliot %A Heyer, Eric %< avec comité de lecture %@ 2271-359X %J OFCE Policy Brief %I OFCE %N 96 %P 1-18 %8 2021-10-22 %D 2021 %K public debt %K Debtwatch %K simulations %K calculation %K developed countries %Z Humanities and Social Sciences/Economics and FinanceJournal articles %X We propose a definition of public debt sustainability based on the possibility of conducting a fiscal effort or giving support to a macroeconomic path that makes it possible to reach a public debt target over a given horizon. The concepts of a fiscal effort and a macroeconomic trajectory are both speculative, as they rely on the anticipation of unknown futures. By making the parameters of these futures explicit and using them in a parsimonious model, we can generate trajectories that are not forecasts but a means of assessing the effort required to reach a targetthat is conditional on explicit assumptions. Debtwatch is a web applicatio n, freely accessible at https://ofce.shinyapps.io/debtwatchr, that can be used to carry out simulations, not only for France but also for other European countries and certain non-European countries such as the United States, including by modifying the parameters and exchanging assumptions with others. It is possible to carry out a calculation that is transparent (the assumptions are known and can be shared) an d reproducible (the sa me assumptions lead to the same results) and which shouldhelp to further the debate on public debt targets and the associated efforts for a selection of developed countries. %G English %2 https://sciencespo.hal.science/hal-03477397/document %2 https://sciencespo.hal.science/hal-03477397/file/OFCEpbrief96.pdf %L hal-03477397 %U https://sciencespo.hal.science/hal-03477397 %~ SHS %~ SCIENCESPO %~ AO-ECONOMIE %~ OFCE %~ SCPO_OA %~ SCPO-REPEC