Martin Mac said:It seems like those songs stayed around on the charts so long due to there being either no recurrent rules or much more relaxed recurrent rules. However, I must say, their reign in the Top 20 was much longer than most songs today.
I don't think we will ever see a song today run on the charts that long due to today's songs on CHR being removed from the current chart after they fall below #15 if they've been on the chart for more than 20 weeks.
Yes, because of the longevity in some of those records during that time, the rules were changed to prevent that from happening again. But I think we can both agree that "The Sign" had a longer lifespan as a current than say "Teenage Dream" or "California Gurls".
This was the closest apples to apples comparison that I could think of:
"The Sign": http://wweb.uta.edu/faculty/gghunt/charts/Songruns/Aceofbase/sign.htm (23 weeks in top 20; #1 for 9 weeks)
"California Gurls": http://wweb.uta.edu/faculty/gghunt/charts/Songruns/P/KatyPerry/californiagurls.htm (19 weeks in top 20; #1 for 7 weeks)
By the way, the record with the longest shelf life seems to be "Another Night": http://wweb.uta.edu/faculty/gghunt/charts/Songruns/R/realmccoyanother_night.htm
It spent 24 weeks in the top 10! Granted, as Atlantaboy mentioned, CHR needed to hang onto the available pop/dance product as much as possible. However, I don't think we will ever see a song stay in the top 10 for 24 weeks ever again. The spin count is too high and listeners attention span is too short these days.