Wireless Sensor Network (WSN) is used for the monitoring and control applications where sensor nodes gather data and send it to the sink. Most of the energy of these nodes is consumed in transmission of data packets without aggregation to sink, which may be located at single or multi hop distance. The direct transmission of data packets to the sink from nodes in the network causes increased communication costs in terms of energy, average delay and network life time. In this context the data aggregation techniques minimize the communication cost with efficient bandwidth utilization by decreasing the packet count reached at the sink. Here we propose Two Tier Cluster based Data Aggregation (TTCDA) algorithm for the randomly distributed nodes to minimize computation and communication cost. The TTCDA is energy and bandwidth efficient, since it reduces the transmission of number of packets to the sink. It is based on the additive and divisible aggregation functions at Cluster head. The functions are applied according to data packets generated by each node by considering spatial and temporal correlation. The aggregation function used in TTCDA effectively reduces the packet count reported to the sink and prevent transmission of redundant data packets by improving energy consumption. The performance of algorithm is validated using examples and simulations.