Business did not operate for the last 3 years but may in future. Should I continue to report depreciation on schedule C?

If you are no longer in business, you should not be continuing to take depreciation on assets. The IRS has a checklist of items that constitute a business and if you do not qualify, it is considered to be a hobby. One of the foremost is that you show a profit in 3 out of every 5 years. 

In order to make this determination, taxpayers should consider the following factors:

• Does the time and effort put into the activity indicate an intention to make a profit?
• Does the taxpayer depend on income from the activity?
• If there are losses, are they due to circumstances beyond the taxpayer’s control or did they occur in the start-up phase of the business?
• Has the taxpayer changed methods of operation to improve profitability?
• Does the taxpayer or his/her advisors have the knowledge needed to carry on the activity as a successful business?
• Has the taxpayer made a profit in similar activities in the past?
• Does the activity make a profit in some years?

From <https://www.irs.gov/uac/business-or-hobby-answer-has-implications-for-deductions>