The last edition of the 1564 psalter with music was issued in 1640. However, there had been many attempts to supplant the 1564 edition, including those by none other than James VI/I. Even so, Scots clung to their beloved psalter until the Westminster assembly promised a potential union between the English and Scottish psalters. A complete psalter by Francis Rous, an English member of Parliament, was revised by the Westminster Assembly but did not satisfy the Scots. Over a period of 2 years and 4 months it was revised by direction of the General Assembly, and it has been calculated that about 40% of the lines are original to the Scottish revisors with only 10% from Rous and 30% from the Westminster Version. Accuracy of translation was in the forefront. This psalter continues in use until the present day in parts of Scotland (especially the Highlands), and around the world in some of the smaller Presbyterian denominations.