Toto iv is the fourth studio album by american rock band toto released in the spring of 1982 by columbia records.The lead single, "rosanna", peaked at number 2 for five weeks on the billboard hot 100 charts, while the album's third single, "africa", topping the hot 100 chart, became the group's first and only number 1 hit.Both songs were hits in the uk as well, reaching number 12 and 3, respectively.The fourth single, "i won't hold you back", also peaked within the top ten on the hot 100, at number 10, but atop the billboard adult contemporary charts for three weeks.It also went into the top 40 in the uk.Wth the success of "africa", the album climbed back into the top 10 in early 1983 on both sides of the atlantic.