Get access to the GitHub archive BigQuery dataset.
Run the following query, update the regex if needed.
SELECT STRFTIME_UTC_USEC(repository_created_at, '%Y-%m') as month,
COUNT(repository_url)
FROM
(SELECT repository_created_at, repository_url
FROM
(TABLE_QUERY([githubarchive:month], 'REGEXP_MATCH(table_id, r"^(201([1-4]))")')))
,
(SELECT STRING(created_at) as repository_created_at, repo_url as repository_url
FROM
(TABLE_QUERY([githubarchive:month], 'REGEXP_MATCH(table_id, r"^(201(5|6))")')))
WHERE repository_created_at IS NOT NULL
GROUP BY month
LIMIT 100You can find the results in the results.json file below.
Note, that the dataset does not contain all the repositories, but only the ones that had activity within the period of the specified dataset.