function rivaluta()
{
coe=new Array(46.233,45.269,44.010,40.394,38.500,36.147,35.019,33.194,31.563,31.651,33.093,34.138,   
34.749,35.122,34.206,34.080,34.523,34.799,36.568,35.111,34.270,34.779,34.548,34.221,   
33.752,33.934,33.786,33.305,33.338,33.719,34.683,34.270,34.438,35.215,35.127,35.397,   
35.534,35.445,35.935,35.408,35.350,34.886,34.881,34.275,33.605,34.017,33.671,33.591,   
33.121,32.539,32.362,31.647,31.609,31.192,31.204,31.315,31.327,31.241,31.050,31.066,   
31.164,30.822,30.731,30.585,30.468,30.268,30.195,30.180,29.964,29.908,29.870,29.983,   
30.028,29.971,29.975,29.685,29.509,29.425,29.870,29.956,29.822,29.707,29.564,29.633,   
29.593,29.469,29.556,29.371,29.000,28.763,28.659,28.687,28.728,28.777,28.646,28.604,   
28.615,28.680,28.615,28.380,28.123,27.935,28.037,27.991,28.077,28.083,27.965,27.780,   
27.587,27.223,26.904,26.741,26.601,26.711,26.771,26.759,26.687,26.834,26.804,26.661,   
26.401,26.560,26.690,26.708,26.613,26.560,26.398,26.375,26.253,26.042,25.858,25.711,   
25.454,25.560,25.524,25.127,24.868,24.701,24.762,24.876,24.956,25.199,25.289,25.416,   
25.316,25.389,25.459,25.413,25.343,25.348,25.378,25.340,25.217,25.051,24.894,24.816,   
24.620,24.719,24.809,24.765,24.660,24.564,24.498,24.539,24.559,24.551,24.438,24.373,   
24.181,24.169,24.154,24.008,23.924,23.886,23.915,23.869,23.798,23.763,23.584,23.475,   
23.265,23.242,23.108,22.821,22.821,22.712,22.626,22.669,22.562,22.477,22.393,22.164,   
21.800,21.410,21.314,21.201,21.201,21.201,21.220,21.182,20.977,20.777,20.777,20.651,   
20.457,20.404,20.317,20.231,20.146,19.961,19.845,19.812,19.730,19.617,19.537,19.457,   
19.362,19.331,19.284,19.238,19.176,19.130,19.069,19.054,19.023,19.008,18.993,18.918,   
18.858,18.858,18.843,18.784,18.740,18.754,18.740,18.754,18.754,18.696,18.637,18.579,   
18.532,18.550,18.514,18.477,18.441,18.405,18.369,18.333,18.261,18.279,18.279,18.279,   
18.208,18.226,18.208,18.173,18.155,18.173,18.191,18.173,18.138,18.120,18.103,18.033,   
17.981,17.981,17.913,17.827,17.794,17.726,17.610,17.560,17.511,17.430,17.365,17.285,    
17.190,17.065,17.019,16.942,16.881,16.850,16.820,16.775,16.641,16.568,16.480,16.408,   
16.347,16.300,16.221,16.174,16.081,16.035,15.974,15.944,15.839,15.765,15.720,15.691,   
15.604,15.517,15.474,15.432,15.333,15.250,15.181,15.099,14.951,14.754,14.651,14.613,   
14.437,14.302,14.182,14.016,13.820,13.730,13.663,13.596,13.531,13.380,13.232,13.017,   
12.848,12.635,12.275,12.125,11.952,11.727,11.448,11.218,10.863,10.643,10.484,10.393,   
10.272,10.154,10.142,10.003,9.938,9.839,9.782,9.731,9.641,9.521,9.441,9.352,   
9.259,9.108,8.920,8.662,8.518,8.479,8.428,8.357,8.210,7.942,7.777,7.681,   
7.654,7.484,7.372,7.296,7.202,7.135,7.081,7.034,6.958,6.884,6.784,6.752,   
6.687,6.619,6.552,6.481,6.412,6.359,6.311,6.283,6.200,6.132,6.079,6.035,   
5.921,5.835,5.763,5.670,5.598,5.543,5.492,5.439,5.309,5.188,5.121,5.039,   
4.878,4.795,4.751,4.677,4.636,4.593,4.517,4.471,4.378,4.304,4.216,4.162,   
4.107,4.034,3.977,3.922,3.868,3.829,3.797,3.771,3.718,3.647,3.586,3.549,   
3.502,3.457,3.426,3.395,3.357,3.325,3.277,3.218,3.173,3.112,3.072,3.051,   
3.008,2.969,2.942,2.912,2.884,2.867,2.840,2.830,2.793,2.747,2.719,2.706,   
2.674,2.646,2.627,2.609,2.594,2.579,2.571,2.563,2.545,2.519,2.504,2.487,   
2.461,2.436,2.419,2.399,2.385,2.372,2.365,2.360,2.350,2.322,2.306,2.291,   
2.280,2.265,2.256,2.250,2.241,2.233,2.233,2.228,2.222,2.210,2.202,2.195,   
2.181,2.173,2.165,2.159,2.152,2.144,2.138,2.132,2.117,2.098,2.093,2.089,   
2.078,2.073,2.064,2.056,2.051,2.044,2.039,2.030,2.020,2.004,1.988,1.981,   
1.966,1.950,1.940,1.928,1.920,1.911,1.906,1.903,1.894,1.876,1.868,1.860,   
1.848,1.836,1.829,1.822,1.816,1.810,1.803,1.791,1.781,1.766,1.755,1.748,   
1.736,1.720,1.715,1.708,1.702,1.692,1.689,1.685,1.678,1.664,1.653,1.649,   
1.636,1.632,1.625,1.618,1.610,1.604,1.601,1.600,1.595,1.586,1.576,1.574,   
1.568,1.562,1.559,1.553,1.547,1.540,1.534,1.532,1.531,1.521,1.513,1.513,   
1.505,1.499,1.496,1.492,1.487,1.484,1.480,1.477,1.473,1.465,1.460,1.454,   
1.449,1.437,1.426,1.418,1.410,1.402,1.401,1.396,1.393,1.385,1.377,1.375,   
1.373,1.369,1.365,1.357,1.352,1.349,1.352,1.351,1.347,1.345,1.342,1.340,   
1.338,1.336,1.335,1.334,1.330,1.330,1.330,1.330,1.328,1.324,1.320,1.320,   
1.316,1.313,1.313,1.310,1.308,1.307,1.307,1.305,1.304,1.302,1.301,1.301,   
1.299,1.297,1.295,1.290,1.288,1.288,1.285,1.285,1.282,1.279,1.275,1.274,   
1.272,1.267,1.263,1.262,1.259,1.254,1.252,1.252,1.250,1.246,1.241,1.240,   
1.234,1.230,1.229,1.225,1.222,1.219,1.219,1.219,1.218,1.215,1.213,1.212,   
1.207,1.203,1.200,1.197,1.195,1.192,1.191,1.189,1.187,1.184,1.181,1.180,   
1.176,1.174,1.170,1.168,1.167,1.166,1.163,1.161,1.158,1.157,1.154,1.154,   
1.152,1.149,1.148,1.145,1.143,1.140,1.139,1.138,1.138,1.138,1.135,1.135,   
1.135,1.131,1.129,1.126,1.124,1.122,1.119,1.118,1.117,1.115,1.115,1.113,   
1.111,1.108,1.106,1.104,1.100,1.099,1.097,1.095,1.095,1.097,1.096,1.095,   
1.094,1.092,1.090,1.088,1.085,1.082,1.080,1.078,1.078,1.075,1.071,1.067,   
1.064,1.061,1.056,1.053,1.048,1.043,1.038,1.038,1.040,1.040,1.044,1.045,   
1.048,1.045,1.045,1.043,1.041,1.039,1.039,1.035,1.038,1.038,1.037,1.035,   
1.034,1.032,1.030,1.026,1.025,1.025,1.022,1.020,1.023,1.020,1.020,1.016,   
1.012,1.009,1.005,1);
coe.reverse();

coe2=new Array (7949.2805,7901.1030,8137.8402,8367.6637,8509.6736,8421.7183,8219.9369,7901.1030,7853.5060,7741.5796,7509.6889,6644.6585,6267.7019,6120.5728,7147.3794,6754.8290,6492.4402,6740.8583,6825.5602,6584.2525,7039.3197,7210.6305,7449.6114,7597.2145,7432.6226,7441.1073,7458.1350,7365.4350,7242.6778,6994.0021,7016.5877,7077.5353,7234.6393,7266.9008,7307.6345,7340.5518,7357.1219,7307.6345,7424.1572,7390.4875,7382.1178,7432.6226,7218.6157,7131.7396,7123.9454,6994.0021,6678.6988,6747.8364,6941.8637,6754.8290,6590.9100,6531.4729,6518.4100,6518.4100,6091.9720,4868.1180,3441.6103,2468.1598,2431.3353,1850.2441,1563.9179,1573.3551,1582.5225,1528.7078,1360.8372,1261.5464,1379.8497,1488.9013,1465.4699,1513.4456,1675.2531,1720.3510,1828.4460,1927.9533,1900.9653,1767.4648,1614.6668,1499.5192,1436.0894,1230.5852,1063.5357,920.1595,548.6877,123.4688,62.6891,53.1178);
coe2.reverse();

lire=document.forms[0].lire[0].checked;
somma=parse(document.forms[0].somma.value+"");
anno=document.forms[0].anno.value;
mese=document.forms[0].mese.value;

if (somma&&isNum(anno))
	{
	document.forms[0].somma.value=punt(virg(somma+""));
	if ((anno>2011)||(anno<1861))
		{
		alert ("Inserire un anno dal 1861 al 2011");
		document.forms[0].reset();
		}
	else
		{
		if (anno>2001&&lire)
			{
			alert("Dal 2002 la lira non circola più\nImporto convertito in euro");
			document.forms[0].lire[1].checked=true;
			somma=round2(somma/1936.27);
			lire=false;
			document.forms[0].somma.value=punt(virg(somma));
			}
		if (anno<2002&&!lire)
			{
			alert("Prima del 2002 l'euro non circolava\nImporto convertito in lire");
			document.forms[0].lire[0].checked=true;
			somma=Math.round(somma*1936.27);
			lire=true;
			document.forms[0].somma.value=punt(somma+"");
			}
		if (anno < 1947) 
			{
			dif=1946-anno; 
			vallire=somma*coe2[dif]*1.095712253 //riporta i coeff. di coe2 al 2005 con ulteriori decimali aggiunti ;
			coef=coe2[dif]*1.095712253;		// per ottenere esattamente quelli della tabella Istat aggiornata		
			}
		else
			{
			dif=(2011*12+4)-(anno*12+eval(mese));
			vallire=somma*coe[dif];
			coef=coe[dif];
			}
		document.forms[0].incre.value=virg(round4(coef));
		if (lire)
			{
			document.forms[0].vallire.value=punt(Math.round(vallire)+"");
			document.forms[0].valeuro.value=punt(virg(round2(vallire/1936.27)));
			}
		else 
			{
			document.forms[0].vallire.value="non disp.";
			document.forms[0].valeuro.value=punt(virg(round2(vallire)));
			}

		}
	}
else 
	{
	alert("È presente un valore non numerico o scorretto\noppure c'è un errore nei separatori delle migliaia\nPremere OK per ricominciare");
	document.forms[0].reset();
	}
}