MARKWEST ENERGY PARTNERS L P

CUSIP: 570759100 Class: UNIT LP PARTN

CUSHING ASSET MANAGEMENT, LP dba NXG INVESTMENT MANAGEMENT's Holding History (CIK: 0001329375)

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

Q3 2015
Shares 1,445,923 Value ($000) $62,044 Avg Close — Range —
Q2 2015
Shares 1,357,615 Value ($000) $76,542 Avg Close — Range —
Q1 2015
Shares 1,169,382 Value ($000) $77,297 Avg Close — Range —
Q4 2014
Shares 1,579,911 Value ($000) $106,155 Avg Close — Range —
Q3 2014
Shares 1,764,087 Value ($000) $135,517 Avg Close — Range —
Q2 2014
Shares 1,736,646 Value ($000) $124,305 Avg Close — Range —
Q1 2014
Shares 1,065,186 Value ($000) $69,578 Avg Close — Range —
Q4 2013
Shares 1,118,690 Value ($000) $73,979 Avg Close — Range —
Q3 2013
Shares 976,386 Value ($000) $73,006 Avg Close — Range —
Q2 2013
Shares 1,101,386 Value ($000) $73,572 Avg Close — Range —