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SHORT-TERM DEBT AND LINES OF CREDIT - SHORT-TERM BORROWINGS (Details) - USD ($) $ in Millions | 6 Months Ended |
--- | --- | ---
Jun. 30, 2017 | Dec. 31, 2016
Short-term borrowings |  |
Commercial Paper | $ 774.8 | $ 860.2
Commercial paper |  |
Short-term borrowings |  |
Weighted-average interest rate on amounts outstanding | 1.42% | 0.96%
Average amounts outstanding during the period | $ 655.5 |
Weighted-average interest rate during the period | 1.09% |

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