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                                                                   Exhibit 99.1

                        CITIZENS BANKING CORPORATION AND
                               F&M BANCORPORATION
                           ANNOUNCE AGREEMENT TO MERGE

April 19, 1999

FLINT, MICHIGAN AND KAUKAUNA, WISCONSIN, Robert J. Vitito, President and Chief
Executive Officer of Citizens Banking Corporation (NASDAQ: CBCF), and Gail E.
Janssen, Chairman of the Board of F&M Bancorporation, today announced the
signing of a definitive agreement whereby Citizens would acquire F&M in a
stock-for-stock merger transaction.

F&M is the fourth largest bank holding company headquartered in Wisconsin and is
the parent company of 23 banking subsidiaries. F&M also has a pending
acquisition creating their 24th banking subsidiary that is scheduled to close
during the second quarter of 1999. F&M has $2.4 billion in total assets and
serves customers at over 80 locations throughout Wisconsin, Iowa, and Minnesota.
F&M's primary markets include the Fox Valley region of east central Wisconsin,
from Green Bay to Appleton to Oshkosh, which is considered one of the fastest
growing areas of Wisconsin. F&M's other primary markets include central
Wisconsin, the southern counties of Wisconsin which border Illinois, and the
northeast quadrant of Iowa.

Superior financial performance ranks F&M among the best performers within its
peer group. Financial performance ratios for F&M's fiscal year ended December
31, 1998 include ROA of 1.43%, ROE of 14.58%, and a 53% efficiency ratio. In
addition, the company displays strong capital and credit quality attributes with
a shareholders' equity-to-assets ratio of 9.86%, net charge-offs of 0.12%, and
loan loss reserve-to-total loans ratio of 1.39%.

Citizens Banking Corporation is the third largest bank holding company
headquartered in Michigan, with assets of $4.5 billion. Citizens provides a full
range of commercial, consumer, mortgage banking, trust and financial planning
services to a broad client base through 123 branch, private banking, and
financial center locations throughout Michigan and in suburban Chicago,
Illinois. Citizens has a significant presence in its key markets, with leading
deposit market share in over half of the counties served. Financial performance
ratios as of March 31, 1999 include ROA of 1.29%, ROE of 13.50%, and an
efficiency ratio of 58%. Citizens also exhibits strong capital and credit
quality attributes with a shareholders' equity-to-assets ratio of 9.57%, net
charge-offs of 0.54%, non-performing assets to total assets of 0.46%, and loan
loss reserve-to-total loans ratio of 1.28%.

Including F&M's pending acquisition of Community Bank of Elkhorn, the combined
entity will have total assets of $7.0 billion, including loans of $5.3 billion
and total deposits of $5.9 billion. The resulting company will be well
capitalized with total shareholders' equity of $689 million. The combined
entities will have over 200 offices, 210 ATMs, and serve 535,000 households in
the five-state region of the upper Midwest. The combined company is also
expected to have a market capitalization of nearly $1.6 billion.



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Mr. Vitito commented, "We are very excited about the opportunities that an
affiliation with F&M provides both organizations. This affiliation will not only
combine two strong companies with similar strategic philosophies, it will expand
delivery of financial services to five states in the Midwest; and provide
additional opportunities for future revenue growth. We look forward to working
with F&M's management team in combining our two fine operations."

Mr. Janssen commented, "Citizens is an excellent company with which we enjoy a
mutual respect. This should help to provide a solid foundation on which to build
this new partnership in expanding services to customers of both organizations.
Over the past 18 years, F&M has been a highly successful company with strong
financial performance and asset growth. Our success in building this company has
enabled our board to affiliate with a very successful merger partner.
Additionally, both companies share similar strategic and community banking
philosophies with stock and dividend performance that have a strong track record
of competitive returns for their shareholders."

Under the terms of the agreement, shareholders of F&M will receive 1.303 shares
of Citizens common stock for each outstanding common share of F&M. Based on
Citizens closing price of $39.00 per share, the transaction has an aggregate
value of $820 million. The transaction will be accounting for as a pooling of
interests and is anticipated to be a tax-free exchange of shares for F&M
shareholders. The transaction is subject to approval by regulatory authorities,
the shareholders of both Citizens and F&M, and the satisfactory completion of
credit due diligence by Citizens. The merger is expected to close in the fourth
quarter of 1999.




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