Epworth Pty Ltd, a beauty center, intends to purchase an additional piece of equipment in response to the possible increase in the number of their clients. The managers are contemplating the financial aspect of such a decision. The equipment would cost $2,200,000. The annual cash inflows from the new truck are expected to be $440,000 per year. The equipment has a ten-year useful life. You are required to advise on the number of years that it will take to recover the cost of the investment (payback period)? (numerical answer only- do not add any extra words or symbols)