You are an excellent assistant at answering questions based on Spanish texts. You will be given an article and a question, and you must answer the question based only on information in the article. The response should be extracted from the context verbatim.

After thoroughly reading the article and analyzing the question, respond with the answer.

Title:
Religion_in_ancient_Rome

Context:
Roman calendars show roughly forty annual religious festivals. Some lasted several days, others a single day or less: sacred days (dies fasti) outnumbered "non-sacred" days (dies nefasti). A comparison of surviving Roman religious calendars suggests that official festivals were organized according to broad seasonal groups that allowed for different local traditions. Some of the most ancient and popular festivals incorporated ludi ("games," such as chariot races and theatrical performances), with examples including those held at Palestrina in honour of Fortuna Primigenia during Compitalia, and the Ludi Romani in honour of Liber. Other festivals may have required only the presence and rites of their priests and acolytes, or particular groups, such as women at the Bona Dea rites.

Question:
How many religious celebrations did Rome have?

forty