This report assesses the presence of revenue forecast bias as a key factor for undermining budget credibility in three African countries - Rwanda, Senegal, and Uganda - based on a newly created database derived from CABRI’s “Budgets in Africa”. Despite the existence of key Public Financial Management (PFM) diagnostic tools such as Public Expenditure and Financial Accountability (PEFA), limited research has examined how effective budgets are in anticipating the fiscal trajectories in the upcoming year or how credible are the economic and revenue estimates underpinning expenditure appropriations. Some research has started to explore these issues empirically, but analyses of developing country contexts remain limited, primarily due to the paucity of relevant data. Whereas earlier studies on budget credibility largely relied on information compiled based on international classifications and diagnostics, this new database compares ex-ante revenue and expenditure forecasts and their ex-post realization through original budget documents - the budget law as approved by the legislature and the final accounts submitted after the conclusion of the fiscal year.