WILLBROS GROUP INC DEL

CUSIP: 969203108 Class: COMMON STOCK

Municipal Employees' Retirement System of Michigan's Holding History (CIK: 0001588873)

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

Q3 2015
Shares 169,700 Value ($000) $214 Avg Close — Range —
Q2 2015
Shares 271,700 Value ($000) $348 Avg Close — Range —
Q1 2015
Shares 271,700 Value ($000) $899 Avg Close — Range —
Q4 2014
Shares 271,700 Value ($000) $1,704 Avg Close — Range —