1. A computer implemented method for preserving privacy of one-dimensional nonstationary data streams, the computer implemented method comprising: a computer processor configured to perform receiving a one-dimensional nonstationary data stream comprising time dependent data from a one-dimensional domain; calculating, for a given instant of sub-space of time, a set of first-moment statistical values for the time series data wherein the first moment statistical values include a principal component for the sub-space of time; and perturbing the data with noise along the principal component in proportion to the first-moment of statistical values so that at least part of a set of second-moment statistical values for the time series data is perturbed by the noise only within a predetermined variance, wherein an output data stream generated based on the perturbing comprises a one-to-one correspondence to the one-dimensional nonstationary data stream that was received.