As there been any change in referral patterns to 5 South England Chiropractic Clinics over the last 10 years

Chiropractic is the field. Data which i will provide needs to be analysed and represented in graph format and using SPSS. The methodology will be literally what has been done with the data, as the data was provided to me and therefore I have not gone out the retrieve it.
Harvard reference, with a completed list and knowledge of where to get specific literature as need to read myself and become familiar with references