Random thought: I sat down with a cyber-security expert for breakfast (Gyro omelette was delicious) this morning and learned that there is a huge percentage of employees (as in more than 60%) are taking spreadsheets and other downloadable forms of data when they depart companies. Sometimes this is because they don't know that it's wrong and sometimes they wish to take data that they "created" to their next job.
I immediately started thinking about the "stuff" that companies typically keep in spreadsheets (quoting calculators, contact lists, bill's of material, etc). Spreadsheets also tend to contain not only data but formulas for calculating value and justifying value of products to the market.
Make sure you take the time to set up your policies and educate your employees on data theft and the consequences that it can bring.
It is all the more important then to ensure that company critical systems, processes and data not be managed and distributed via spreadsheets. Think about converting some of those spreadsheets to a more secure database that has 100% traceability and ping me if you need help. These days it is incredibly simple, fast and cheap to transition spreadsheets to purpose built applications.