In contrast to the random deployment method for wireless sensor networks, there are various applications that require manual deployment. While the deployment is costly and usually there is no change in the position of the nodes, it is better to evaluate the deployment scheme before doing it. There are different existing metrics to evaluate a deployment including coverage, connectivity, network lifetime, and cost. With emerging real applications of WSNs, it has become a must to evaluate the deployments with more realistic metrics and model. In this paper we have proposed an accumulative path reliability rate metric, regarding the hop-based nature of routing in these networks, to measure the connectivity between two nodes that are not adjacent. We have applied the metric to existing deployment methods and analysed the results.