Billboard used to have a rule that if a song wasn't top 75 on the airplay chart and didn't have a physical single, it was ineligible to chart at all on the Hot 100. As an example:
Song A: 23 million audience impressions + no physical release (#76 on airplay chart)
Song B: 13 million audience impressions + 6,521 single sales (#98 on airplay chart)
Song B would chart on the Hot 100 but Song A would not, despite Song A still having more points. This is how songs like "My Prerogative" and "I'm Not a Girl, Not Yet a Woman" were unable to chart on the Hot 100 but "Outrageous" and "Overprotected" were, even though the latter two had less airplay. This was changed in 2005 when digital sales were added.
"Rumors" was #81 or something like that in airplay but because it didn't have a physical single, it couldn't chart.
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But I could have sworn "Rumors" was a huge hit. 
The song was all over NY radio in late 2004. 