Sound Ledger¹ (Superman, Noise, Silence)

29: The number of fighting types represented by onomatopoeia found in the comic Superman: The Doomsday Wars comic

300,000: Penalty (in $US) for noise (and dust) pollution for the owner and operator of a scrap metal facility in Massachusetts

40: Percent of surveyed travelers who reported interest “in booking a silent retreat”

. . .

¹Footnotes: Superman: traverse.asia (Thanks, Mike Rhode!). Penalty: mass.gov. Retreat: cntraveler.com.