, ▁A - 1 0 ▁Th under bol t ▁II , ▁P - 5 1 ▁Must ang , ▁P - 4 0 ▁War h awk ) ▁ ▁" Back ▁Home ▁Again ▁in ▁Indiana " ▁ ▁The ▁most ▁traditional ▁performance ▁is ▁the ▁singing ▁of ▁" Back ▁Home ▁Again ▁in ▁Indiana ". ▁This ▁tradition ▁has ▁accompanied ▁the ▁race ▁since ▁ 1 9 4 6 . ▁Jim ▁N ab ors , ▁accompanied ▁by ▁the ▁Pur due ▁March ing ▁Band , ▁not ably ▁performed ▁the ▁song ▁in ▁most ▁years ▁from ▁ 1 9 7 2 ▁to ▁ 2 0 1 4 . ▁The ▁song ▁has ▁long ▁been ▁the ▁last ▁event ▁in ▁the ▁order ▁of ▁the ▁day , ▁immediately ▁preceding ▁the ▁command ▁to ▁start ▁engines . ▁ ▁During ▁the ▁song , ▁thousands ▁of ▁mult icol ored ▁bal lo ons ▁are ▁released ▁from ▁an ▁in field ▁tent . ▁The ▁bal lo on ▁release ▁dates ▁back ▁to ▁ 1 9 4 7 , ▁and ▁has ▁coinc ided ▁with ▁the ▁song ▁since ▁about ▁ 1 9 5 0 . ▁The ▁song , ▁which ▁was ▁first ▁published ▁in ▁ 1 9 1 7 , ▁is ▁reported ▁to ▁have ▁been ▁first ▁played ▁at ▁the ▁race ▁in ▁ 1 9 1 9 . ▁A ▁track ▁side ▁br ass ▁band ▁played ▁the ▁song ▁as ▁Indiana - born ▁How dy ▁Wil co x ▁was ▁finishing ▁the ▁final ▁la ps ▁to ▁victory . ▁ ▁In ▁ 1 9 8 6 , ▁the ▁race ▁was ▁ra ined ▁out ▁on ▁Sunday ▁and ▁Monday , ▁and ▁subsequently ▁post pon ed