IR has several classes of travelwith or without air conditioning; a train may include just one or several of these. Slow passenger trains have only unreserved seating class whereas Rajdhani, Duronto, Shatabdi, Garib Rath and Yuva trains only have air-conditioned classes. The fares are different for each class, with unreserved seating class being the cheapest. The fare of Rajdhani, Duronto and Shatabdi trains includes food served in the train, but for other trains food has to be bought separately. In September 2016, the IR introduced dynamic fares for all accommodation classes for Rajdhani, Duronto and Shatabdi trains (except 1AC and EC classes) to shore up revenue. In long-distance trains a pantry car is usually included and the food is served at the berth or seat itself. Luxury trains such as Palace on Wheels have separate dining cars but fares are comparable to a five-star hotel.