Which design pattern I will use in report generation? [on hold]

I want to know how can I implement my below scenario into design pattern for report generation.

Scenario like : I have four different types of report like Report1, Report2, Report3 and Report4 and in future many other reports will come. All the reports logic are different So I would like to make individual class for all report. And also output of each report is generated in either HTML or PDF and in future Excel. Like some interface that we implement on each class the some common method to generate report etc..

So I can I make structured design pattern of above scenario.

Give me your suggestions on this.