Shaul Sapir, who was editor of the Deer Amerikaner in the early 20th century, was once asked about the Jewish Publishing Situation in the United States.
He replied "כי מלאה הארץ חמ"ס "
חמס ראשי תבות חומשים מחזורים סדורים
How very true! 99% of the Hebrew books printed in America before WWI were Prayerbooks or Chumashim.