BLACK HILLS CORP

CUSIP: 92113109 Class: COM

GROUP ONE TRADING, L.P.'s Holding History (CIK: 0000932540)

Note: Option positions (PUT/CALL) are excluded.

Q4 2014
Shares 1,459 Value ($000) $77 Avg Close — Range —
Q3 2014
Shares 1,155 Value ($000) $55 Avg Close — Range —
Q4 2013
Shares 1,659 Value ($000) $87 Avg Close — Range —
Q3 2013
Shares 6,598 Value ($000) $329 Avg Close — Range —