Perhaps you should try some spelling variations:
"improving bank performance contract." » "improving bank performance contracts.", "improving market performance contract.", "improving _ performance contract.", "improving firm performance contract.", "improving land performance contract.", "improving urban performance contract.", "improving air performance contract."
"improving basic performance series." » "improving basic performance metrics.", "improving basic performance reviews.", "improving basic performance review.", "improving based performance series.", "improving past performance series.", "improving seismic performance series.", "improving air performance series.", "improve basic performance series.", "improving public performance series."

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