<PAGE>
 
continue to rent a package for a period substantially longer than the initial
term of the contract. Contract compression pricing, which is based on prevailing
market conditions, generally contains provisions for periodic rate adjustments
to reflect market changes.

  Natural gas compressor package rental utilization is affected primarily by the
number and age of producing oil and gas wells, the volume of natural gas
consumed and natural gas prices.  Rental rates for natural gas compressor
packages are determined primarily by the demand for packages and secondarily by
the size and horsepower of a natural gas compressor package.  The following
table compares utilizations and rental rates (on a horsepower basis) and fleet
size for the Energy Industries' fleet of natural gas compressor packages at
September 30, 1993 and 1994 and at June 30, 1995.  The Company did not own
Energy Industries prior to November 1993.

<TABLE>
<CAPTION>
                                                         AS OF SEPTEMBER 30,
                                      AS OF          --------------------------
                                  JUNE 30, 1995        1994              1993
                                  --------------     --------          --------
 
<S>                               <C>                <C>               <C>
FLEET UTILIZATION:
  Horsepower                           81.5%           82.6%               74.4%
MONTHLY RENTAL RATE, BASED ON:
  Horsepower                         $15.54          $16.61              $17.25
FLEET SIZE:
  Number of Units                       771             706                 681
  Horsepower                        129,467         113,786             106,175
</TABLE>

  Utilization of compressor packages increased from 1993 to 1994 in response to
generally strengthening natural gas markets, a return of producer confidence and
greater emphasis being placed on the rental operations.  Changes in rental rates
are primarily caused by the changes in the mix between smaller and higher
horsepower natural gas compressor packages in the fleet.  Growth in the fleet
has resulted from the acquisitions of additional compressors and the
construction of new compressor packages each year, net of retirements and sales
of older equipment from the rental fleet.

  Natural Gas Compressor Package Sales.  In addition to operating a fleet of
natural gas compressor packages for rental purposes, Energy Industries designs,
fabricates and sells natural gas compressor packages designed to customer
specifications.  Energy Industries sells compressor packages to natural gas
producers, gatherers and transmission companies which expect the long life of
their associated reserves or pipeline to justify the capital cost of acquiring,
rather than renting, a natural gas compressor package.  Most of Energy
Industries' natural gas compressor package sales are for larger, high-horsepower
packages.

  Because of the relatively high capital costs associated with these units,
Energy Industries provides a capital lease financing option to its customers.
Under the terms of a typical capital lease, a purchaser will lease the natural
gas compressor package from Energy Industries for a period of between three and
four years at monthly lease rates.  At the termination of the lease, the lessee
has the option to purchase the natural gas compressor package for a nominal
amount or return the natural gas compressor package to Energy Industries.

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