[Help] Sensitivity Analysis

Assume that Y = f(x1,x2) is known. x1 and x2 are random numbers and generated based on given probability distributions. Data are presented as following table.
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x1 x2 Y
0.988050103 0.988855362 2559.5599
1.019544244 1.011857986 2569.6639
1.017633319 0.993216634 2434.7771
1.034118652 0.992662549 2640.2903
1.004858971 0.998409688 2552.73
0.986317515 0.987372577 2499.7608
1.041661263 1.028900743 2589.9709
0.984923542 1.001723289 2476.7094
0.958861113 1.00391221 2463.6914
0.987714708 0.965107799 2449.9718
1.033964276 1.039957404 2516.3216
0.978532553 1.007963538 2531.6713
0.990386009 1.007173538 2517.9594
0.971170902 1.015195489 2565.9091
0.982220113 0.990603924 2519.421
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My question is how to calculate sensitivity of response Y to each factor x1 and x2 ?
Because I want to draw the sensivity chart just like below.