Chinese Calendar Algorithm - Year 1901 to 2100 - v4.15, by Herong Yang
Chinese Calendar Program in java
This section provides a Chinese calendar program in Java language using using astronomical data obtained from eleworld.com.
I have implemented the Chinese calendar algorithm in a Java program, called ChineseCalendar.java:
/**
* ChineseCalendar.java
* Copyright (c) 1997 HerongYang.com, All Rights Reserved.
* Valid for 200 years: from Gregorian year 1901 to 2100
* Not synchronized.
*/
import java.text.*;
import java.util.*;
class ChineseCalendar {
private int gregorianYear;
private int gregorianMonth;
private int gregorianDate;
private boolean isGregorianLeap;
private int dayOfYear;
private int dayOfWeek; // Sunday is the first day
private int chineseYear;
private int chineseMonth; // -n is a leap month
private int chineseDate;
private int sectionalTerm;
private int principleTerm;
private static char[] daysInGregorianMonth =
{31,28,31,30,31,30,31,31,30,31,30,31};
private static String[] monthNames =
{"Jan","Feb","Mar","Apr","May","Jun",
"Jul","Aug","Sep","Oct","Nov","Dec"};
private static String[] stemNames =
{"Wood","Wood","Fire","Fire","Earth","Earth",
"Metal","Metal","Water","Water"};
private static String[] branchNames =
{"Rat","Ox","Tiger","Rabbit","Dragon","Snake",
"Horse","Sheep","Monkey","Rooster","Dog","Boar"};
public static void main(String[] arg) {
ChineseCalendar c = new ChineseCalendar();
String cmd = "day";
int y = 1901;
int m = 1;
int d = 1;
if (arg.length>0) cmd = arg[0];
if (arg.length>1) y = Integer.parseInt(arg[1]);
if (arg.length>2) m = Integer.parseInt(arg[2]);
if (arg.length>3) d = Integer.parseInt(arg[3]);
c.setGregorian(y,m,d);
c.computeChineseFields();
c.computeSolarTerms();
if (cmd.equalsIgnoreCase("year")) {
String[] t = c.getYearTable();
for (int i=0; i<t.length; i++) System.out.println(t[i]);
} else if (cmd.equalsIgnoreCase("month")) {
String[] t = c.getMonthTable();
for (int i=0; i<t.length; i++) System.out.println(t[i]);
} else {
System.out.println(c.toString());
}
}
public ChineseCalendar() {
setGregorian(1901,1,1);
}
public void setGregorian(int y, int m, int d) {
gregorianYear = y;
gregorianMonth = m;
gregorianDate = d;
isGregorianLeap = isGregorianLeapYear(y);
dayOfYear = dayOfYear(y,m,d);
dayOfWeek = dayOfWeek(y,m,d);
chineseYear = 0;
chineseMonth = 0;
chineseDate = 0;
sectionalTerm = 0;
principleTerm = 0;
}
public static boolean isGregorianLeapYear(int year) {
boolean isLeap = false;
if (year%4==0) isLeap = true;
if (year%100==0) isLeap = false;
if (year%400==0) isLeap = true;
return isLeap;
}
public static int daysInGregorianMonth(int y, int m) {
int d = daysInGregorianMonth[m-1];
if (m==2 && isGregorianLeapYear(y)) d++; // Leap year adjustment
return d;
}
public static int dayOfYear(int y, int m, int d) {
int c = 0;
for (int i=1; i<m; i++) { // Number of months passed
c = c + daysInGregorianMonth(y,i);
}
c = c + d;
return c;
}
public static int dayOfWeek(int y, int m, int d) {
int w = 1; // 01-Jan-0001 is Monday, so base is Sunday
y = (y-1)%400 + 1; // Gregorian calendar cycle is 400 years
int ly = (y-1)/4; // Leap years passed
ly = ly - (y-1)/100; // Adjustment
ly = ly + (y-1)/400; // Adjustment
int ry = y - 1 - ly; // Regular years passed
w = w + ry; // Regular year has one extra week day
w = w + 2*ly; // Leap year has two extra week days
w = w + dayOfYear(y,m,d);
w = (w-1)%7 + 1;
return w;
}
private static char[] chineseMonths = {
//Chinese month map, 2 bytes per year, from 1900 to 2100, 402 bytes.
//The first 4 bits represents the leap month of the year.
//The rest 12 bits are flags indicate if the corresponding month
//is a 29-day month. 2 bytes are stored in low-high order.
0x00,0x04,0xad,0x08,0x5a,0x01,0xd5,0x54,0xb4,0x09,0x64,0x05,0x59,0x45,
0x95,0x0a,0xa6,0x04,0x55,0x24,0xad,0x08,0x5a,0x62,0xda,0x04,0xb4,0x05,
0xb4,0x55,0x52,0x0d,0x94,0x0a,0x4a,0x2a,0x56,0x02,0x6d,0x71,0x6d,0x01,
0xda,0x02,0xd2,0x52,0xa9,0x05,0x49,0x0d,0x2a,0x45,0x2b,0x09,0x56,0x01,
0xb5,0x20,0x6d,0x01,0x59,0x69,0xd4,0x0a,0xa8,0x05,0xa9,0x56,0xa5,0x04,
0x2b,0x09,0x9e,0x38,0xb6,0x08,0xec,0x74,0x6c,0x05,0xd4,0x0a,0xe4,0x6a,
0x52,0x05,0x95,0x0a,0x5a,0x42,0x5b,0x04,0xb6,0x04,0xb4,0x22,0x6a,0x05,
0x52,0x75,0xc9,0x0a,0x52,0x05,0x35,0x55,0x4d,0x0a,0x5a,0x02,0x5d,0x31,
0xb5,0x02,0x6a,0x8a,0x68,0x05,0xa9,0x0a,0x8a,0x6a,0x2a,0x05,0x2d,0x09,
0xaa,0x48,0x5a,0x01,0xb5,0x09,0xb0,0x39,0x64,0x05,0x25,0x75,0x95,0x0a,
0x96,0x04,0x4d,0x54,0xad,0x04,0xda,0x04,0xd4,0x44,0xb4,0x05,0x54,0x85,
0x52,0x0d,0x92,0x0a,0x56,0x6a,0x56,0x02,0x6d,0x02,0x6a,0x41,0xda,0x02,
0xb2,0xa1,0xa9,0x05,0x49,0x0d,0x0a,0x6d,0x2a,0x09,0x56,0x01,0xad,0x50,
0x6d,0x01,0xd9,0x02,0xd1,0x3a,0xa8,0x05,0x29,0x85,0xa5,0x0c,0x2a,0x09,
0x96,0x54,0xb6,0x08,0x6c,0x09,0x64,0x45,0xd4,0x0a,0xa4,0x05,0x51,0x25,
0x95,0x0a,0x2a,0x72,0x5b,0x04,0xb6,0x04,0xac,0x52,0x6a,0x05,0xd2,0x0a,
0xa2,0x4a,0x4a,0x05,0x55,0x94,0x2d,0x0a,0x5a,0x02,0x75,0x61,0xb5,0x02,
0x6a,0x03,0x61,0x45,0xa9,0x0a,0x4a,0x05,0x25,0x25,0x2d,0x09,0x9a,0x68,
0xda,0x08,0xb4,0x09,0xa8,0x59,0x54,0x03,0xa5,0x0a,0x91,0x3a,0x96,0x04,
0xad,0xb0,0xad,0x04,0xda,0x04,0xf4,0x62,0xb4,0x05,0x54,0x0b,0x44,0x5d,
0x52,0x0a,0x95,0x04,0x55,0x22,0x6d,0x02,0x5a,0x71,0xda,0x02,0xaa,0x05,
0xb2,0x55,0x49,0x0b,0x4a,0x0a,0x2d,0x39,0x36,0x01,0x6d,0x80,0x6d,0x01,
0xd9,0x02,0xe9,0x6a,0xa8,0x05,0x29,0x0b,0x9a,0x4c,0xaa,0x08,0xb6,0x08,
0xb4,0x38,0x6c,0x09,0x54,0x75,0xd4,0x0a,0xa4,0x05,0x45,0x55,0x95,0x0a,
0x9a,0x04,0x55,0x44,0xb5,0x04,0x6a,0x82,0x6a,0x05,0xd2,0x0a,0x92,0x6a,
0x4a,0x05,0x55,0x0a,0x2a,0x4a,0x5a,0x02,0xb5,0x02,0xb2,0x31,0x69,0x03,
0x31,0x73,0xa9,0x0a,0x4a,0x05,0x2d,0x55,0x2d,0x09,0x5a,0x01,0xd5,0x48,
0xb4,0x09,0x68,0x89,0x54,0x0b,0xa4,0x0a,0xa5,0x6a,0x95,0x04,0xad,0x08,
0x6a,0x44,0xda,0x04,0x74,0x05,0xb0,0x25,0x54,0x03
};
// Base date: 01-Jan-1901, 4598/11/11 in Chinese calendar
private static int baseYear = 1901;
private static int baseMonth = 1;
private static int baseDate = 1;
private static int baseIndex = 0;
private static int baseChineseYear = 4598-1;
private static int baseChineseMonth = 11;
private static int baseChineseDate = 11;
public int computeChineseFields() {
// Gregorian year out of the computation range
if (gregorianYear<1901 || gregorianYear>2100) return 1;
int startYear = baseYear;
int startMonth = baseMonth;
int startDate = baseDate;
chineseYear = baseChineseYear;
chineseMonth = baseChineseMonth;
chineseDate = baseChineseDate;
// Switching to the second base to reduce the calculation process
// Second base date: 01-Jan-2000, 4697/11/25 in Chinese calendar
if (gregorianYear >= 2000) {
startYear = baseYear + 99;
startMonth = 1;
startDate = 1;
chineseYear = baseChineseYear + 99;
chineseMonth = 11;
chineseDate = 25;
}
// Calculating the number of days
// between the start date and the current date
// The following algorithm only works
// for startMonth = 1 and startDate = 1
int daysDiff = 0;
for (int i=startYear; i<gregorianYear; i++) {
daysDiff += 365;
if (isGregorianLeapYear(i)) daysDiff += 1; // leap year
}
for (int i=startMonth; i<gregorianMonth; i++) {
daysDiff += daysInGregorianMonth(gregorianYear,i);
}
daysDiff += gregorianDate - startDate;
// Adding that number of days to the Chinese date
// Then bring Chinese date into the correct range.
// one Chinese month at a time
chineseDate += daysDiff;
int lastDate = daysInChineseMonth(chineseYear, chineseMonth);
int nextMonth = nextChineseMonth(chineseYear, chineseMonth);
while (chineseDate>lastDate) {
if (Math.abs(nextMonth)<Math.abs(chineseMonth)) chineseYear++;
chineseMonth = nextMonth;
chineseDate -= lastDate;
lastDate = daysInChineseMonth(chineseYear, chineseMonth);
nextMonth = nextChineseMonth(chineseYear, chineseMonth);
}
return 0;
}
private static int[] bigLeapMonthYears = {
// The leap months in the following years have 30 days
6, 14, 19, 25, 33, 36, 38, 41, 44, 52,
55, 79,117,136,147,150,155,158,185,193
};
public static int daysInChineseMonth(int y, int m) {
// Regular month: m > 0
// Leap month: m < 0
int index = y - baseChineseYear + baseIndex;
int v = 0;
int l = 0;
int d = 30; // normal month
if (1<=m && m<=8) {
v = chineseMonths[2*index];
l = m - 1;
if ( ((v>>l)&0x01)==1 ) d = 29;
} else if (9<=m && m<=12) {
v = chineseMonths[2*index+1];
l = m - 9;
if ( ((v>>l)&0x01)==1 ) d = 29;
} else { // leap month
v = chineseMonths[2*index+1];
v = (v>>4)&0x0F;
if (v!=Math.abs(m)) {
d = 0; // wrong m specified
} else {
d = 29;
for (int i=0; i<bigLeapMonthYears.length; i++) {
if (bigLeapMonthYears[i]==index) {
d = 30;
break;
}
}
}
}
return d;
}
public static int nextChineseMonth(int y, int m) {
int n = Math.abs(m) + 1; // normal behavior
if (m>0) {
// need to find out if we are in a leap year or not
int index = y - baseChineseYear + baseIndex;
int v = chineseMonths[2*index+1];
v = (v>>4)&0x0F;
if (v==m) n = -m; // next month is a leap month
}
if (n==13) n = 1; //roll into next year
return n;
}
private static char[][] sectionalTermMap = {
{7,6,6,6,6,6,6,6,6,5,6,6,6,5,5,6,6,5,5,5,5,5,5,5,5,4,5,5}, // Jan
{5,4,5,5,5,4,4,5,5,4,4,4,4,4,4,4,4,3,4,4,4,3,3,4,4,3,3,3}, // Feb
{6,6,6,7,6,6,6,6,5,6,6,6,5,5,6,6,5,5,5,6,5,5,5,5,4,5,5,5,5}, // Mar
{5,5,6,6,5,5,5,6,5,5,5,5,4,5,5,5,4,4,5,5,4,4,4,5,4,4,4,4,5}, // Apr
{6,6,6,7,6,6,6,6,5,6,6,6,5,5,6,6,5,5,5,6,5,5,5,5,4,5,5,5,5}, // May
{6,6,7,7,6,6,6,7,6,6,6,6,5,6,6,6,5,5,6,6,5,5,5,6,5,5,5,5,4,5,5,5,5},
{7,8,8,8,7,7,8,8,7,7,7,8,7,7,7,7,6,7,7,7,6,6,7,7,6,6,6,7,7}, // Jul
{8,8,8,9,8,8,8,8,7,8,8,8,7,7,8,8,7,7,7,8,7,7,7,7,6,7,7,7,6,6,7,7,7},
{8,8,8,9,8,8,8,8,7,8,8,8,7,7,8,8,7,7,7,8,7,7,7,7,6,7,7,7,7}, // Sep
{9,9,9,9,8,9,9,9,8,8,9,9,8,8,8,9,8,8,8,8,7,8,8,8,7,7,8,8,8}, // Oct
{8,8,8,8,7,8,8,8,7,7,8,8,7,7,7,8,7,7,7,7,6,7,7,7,6,6,7,7,7}, // Nov
{7,8,8,8,7,7,8,8,7,7,7,8,7,7,7,7,6,7,7,7,6,6,7,7,6,6,6,7,7} // Dec
};
private static char[][] sectionalTermYear = {
{13,49,85,117,149,185,201,250,250}, // Jan
{13,45,81,117,149,185,201,250,250}, // Feb
{13,48,84,112,148,184,200,201,250}, // Mar
{13,45,76,108,140,172,200,201,250}, // Apr
{13,44,72,104,132,168,200,201,250}, // May
{5 ,33,68,96 ,124,152,188,200,201}, // Jun
{29,57,85,120,148,176,200,201,250}, // Jul
{13,48,76,104,132,168,196,200,201}, // Aug
{25,60,88,120,148,184,200,201,250}, // Sep
{16,44,76,108,144,172,200,201,250}, // Oct
{28,60,92,124,160,192,200,201,250}, // Nov
{17,53,85,124,156,188,200,201,250} // Dec
};
private static char[][] principleTermMap = {
{21,21,21,21,21,20,21,21,21,20,20,21,21,20,20,20,20,20,20,20,20,19,
20,20,20,19,19,20},
{20,19,19,20,20,19,19,19,19,19,19,19,19,18,19,19,19,18,18,19,19,18,
18,18,18,18,18,18},
{21,21,21,22,21,21,21,21,20,21,21,21,20,20,21,21,20,20,20,21,20,20,
20,20,19,20,20,20,20},
{20,21,21,21,20,20,21,21,20,20,20,21,20,20,20,20,19,20,20,20,19,19,
20,20,19,19,19,20,20},
{21,22,22,22,21,21,22,22,21,21,21,22,21,21,21,21,20,21,21,21,20,20,
21,21,20,20,20,21,21},
{22,22,22,22,21,22,22,22,21,21,22,22,21,21,21,22,21,21,21,21,20,21,
21,21,20,20,21,21,21},
{23,23,24,24,23,23,23,24,23,23,23,23,22,23,23,23,22,22,23,23,22,22,
22,23,22,22,22,22,23},
{23,24,24,24,23,23,24,24,23,23,23,24,23,23,23,23,22,23,23,23,22,22,
23,23,22,22,22,23,23},
{23,24,24,24,23,23,24,24,23,23,23,24,23,23,23,23,22,23,23,23,22,22,
23,23,22,22,22,23,23},
{24,24,24,24,23,24,24,24,23,23,24,24,23,23,23,24,23,23,23,23,22,23,
23,23,22,22,23,23,23},
{23,23,23,23,22,23,23,23,22,22,23,23,22,22,22,23,22,22,22,22,21,22,
22,22,21,21,22,22,22},
{22,22,23,23,22,22,22,23,22,22,22,22,21,22,22,22,21,21,22,22,21,21,
21,22,21,21,21,21,22}
};
private static char[][] principleTermYear = {
{13,45,81,113,149,185,201}, // Jan
{21,57,93,125,161,193,201}, // Feb
{21,56,88,120,152,188,200,201}, // Mar
{21,49,81,116,144,176,200,201}, // Apr
{17,49,77,112,140,168,200,201}, // May
{28,60,88,116,148,180,200,201}, // Jun
{25,53,84,112,144,172,200,201}, // Jul
{29,57,89,120,148,180,200,201}, // Aug
{17,45,73,108,140,168,200,201}, // Sep
{28,60,92,124,160,192,200,201}, // Oct
{16,44,80,112,148,180,200,201}, // Nov
{17,53,88,120,156,188,200,201} // Dec
};
public int computeSolarTerms() {
// Gregorian year out of the computation range
if (gregorianYear<1901 || gregorianYear>2100) return 1;
sectionalTerm = sectionalTerm(gregorianYear, gregorianMonth);
principleTerm = principleTerm(gregorianYear, gregorianMonth);
return 0;
}
public static int sectionalTerm(int y, int m) {
if (y<1901 || y>2100) return 0;
int index = 0;
int ry = y-baseYear+1;
while (ry>=sectionalTermYear[m-1][index]) index++;
int term = sectionalTermMap[m-1][4*index+ry%4];
// if ((ry == 121)&&(m == 4)) term = 5;
// if ((ry == 132)&&(m == 4)) term = 5;
// if ((ry == 194)&&(m == 6)) term = 6;
return term;
}
public static int principleTerm(int y, int m) {
if (y<1901 || y>2100) return 0;
int index = 0;
int ry = y-baseYear+1;
while (ry>=principleTermYear[m-1][index]) index++;
int term = principleTermMap[m-1][4*index+ry%4];
// if ((ry == 171)&&(m == 3)) term = 21;
// if ((ry == 181)&&(m == 5)) term = 21;
return term;
}
public String toString() {
StringBuffer buf = new StringBuffer();
buf.append("Gregorian Year: "+gregorianYear+"\n");
buf.append("Gregorian Month: "+gregorianMonth+"\n");
buf.append("Gregorian Date: "+gregorianDate+"\n");
buf.append("Is Leap Year: "+isGregorianLeap+"\n");
buf.append("Day of Year: "+dayOfYear+"\n");
buf.append("Day of Week: "+dayOfWeek+"\n");
buf.append("Chinese Year: "+chineseYear+"\n");
buf.append("Heavenly Stem: "+((chineseYear-1)%10)+"\n");
buf.append("Earthly Branch: "+((chineseYear-1)%12)+"\n");
buf.append("Chinese Month: "+chineseMonth+"\n");
buf.append("Chinese Date: "+chineseDate+"\n");
buf.append("Sectional Term: "+sectionalTerm+"\n");
buf.append("Principle Term: "+principleTerm+"\n");
return buf.toString();
}
public String[] getYearTable() {
setGregorian(gregorianYear,1,1);
computeChineseFields();
computeSolarTerms();
String[] table = new String[59]; // 6*9 + 5
table[0] = getTextLine(27,
"Gregorian Calendar Year: "+gregorianYear);
table[1] = getTextLine(27,
"Chinese Calendar Year: "+(chineseYear+1)
+ " ("+stemNames[(chineseYear+1-1)%10]
+ "-"+branchNames[(chineseYear+1-1)%12]+")");
int ln = 2;
String[] mLeft = null;
String[] mRight = null;
for (int i=1; i<=6; i++) {
table[ln] = getTextLine(0,null);
ln++;
mLeft = getMonthTable();
mRight = getMonthTable();
for (int j=0; j<mLeft.length; j++) {
String line = mLeft[j] + " " + mRight[j];
table[ln] = line;
ln++;
}
}
table[ln] = getTextLine(0,null);
ln++;
table[ln] = getTextLine(0,"##/## - Gregorian date/Chinese date,"
+ " (*)CM## - (Leap) Chinese month first day");
ln++;
table[ln] = getTextLine(0,
"ST## - Sectional term, PT## - Principle term");
ln++;
return table;
}
public static String getTextLine(int s, String t) {
String str = " "
+" " + " ";
if (t!=null && s<str.length() && s+t.length()<str.length())
str = str.substring(0,s) + t + str.substring(s+t.length());
return str;
}
public String[] getMonthTable() {
setGregorian(gregorianYear,gregorianMonth,1);
computeChineseFields();
computeSolarTerms();
String[] table = new String[8];
String title = " "
+ monthNames[gregorianMonth-1]
+ " ";
String header = " Sun Mon Tue Wed Thu Fri Sat ";
String blank = " ";
table[0] = title;
table[1] = header;
int wk = 2;
String line = "";
for (int i=1; i<dayOfWeek; i++) {
line += " " + ' ';
}
int days = daysInGregorianMonth(gregorianYear,gregorianMonth);
for (int i=gregorianDate; i<=days; i++) {
line += getDateString() + ' ';
rollUpOneDay();
if (dayOfWeek==1) {
table[wk] = line;
line = "";
wk++;
}
}
for (int i=dayOfWeek; i<=7; i++) {
line += " " + ' ';
}
table[wk] = line;
for (int i=wk+1; i<table.length; i++) {
table[i] = blank;
}
for (int i=0; i<table.length; i++) {
table[i] = table[i].substring(0,table[i].length()-1);
}
return table;
}
public String getDateString() {
String str = "* / ";
String gm = String.valueOf((gregorianMonth-1+11)%12+1);
if (gm.length()==1) gm = ' ' + gm;
String cm = String.valueOf(Math.abs(chineseMonth));
if (cm.length()==1) cm = ' ' + cm;
String gd = String.valueOf(gregorianDate);
if (gd.length()==1) gd = ' ' + gd;
String cd = String.valueOf(chineseDate);
if (cd.length()==1) cd = ' ' + cd;
if (gregorianDate==sectionalTerm) {
str = " ST"+gm;
} else if (gregorianDate==principleTerm) {
str = " PT"+gm;
} else if (chineseDate==1 && chineseMonth>0) {
str = " CM"+cm;
} else if (chineseDate==1 && chineseMonth<0) {
str = "*CM"+cm;
} else {
str = gd+'/'+cd;
}
return str;
}
public int rollUpOneDay() {
dayOfWeek = dayOfWeek%7 + 1;
dayOfYear++;
gregorianDate++;
int days = daysInGregorianMonth(gregorianYear,gregorianMonth);
if (gregorianDate>days) {
gregorianDate = 1;
gregorianMonth++;
if (gregorianMonth>12) {
gregorianMonth = 1;
gregorianYear++;
dayOfYear = 1;
isGregorianLeap = isGregorianLeapYear(gregorianYear);
}
sectionalTerm = sectionalTerm(gregorianYear,gregorianMonth);
principleTerm = principleTerm(gregorianYear,gregorianMonth);
}
chineseDate++;
days = daysInChineseMonth(chineseYear,chineseMonth);
if (chineseDate>days) {
chineseDate = 1;
chineseMonth = nextChineseMonth(chineseYear,chineseMonth);
if (chineseMonth==1) chineseYear++;
}
return 0;
}
}
Table of Contents
Chinese Calendar Background Information
►Chinese Calendar Algorithm and Program
The Gregorian Calendar Algorithm
The Chinese Calendar Algorithm
►Chinese Calendar Program in java
How to Use Chinese Calendar Program
Chinese Calendar Format and Notations
Corrections on the Astronomical Data
Chinese Calendars: Year 1901 to 1910
Chinese Calendars: Year 1911 to 1920
Chinese Calendars: Year 1921 to 1930
Chinese Calendars: Year 1931 to 1940
Chinese Calendars: Year 1941 to 1950
Chinese Calendars: Year 1951 to 1960
Chinese Calendars: Year 1961 to 1970
Chinese Calendars: Year 1971 to 1980
Chinese Calendars: Year 1981 to 1990
Chinese Calendars: Year 1991 to 2000
Chinese Calendars: Year 2001 to 2010
Chinese Calendars: Year 2011 to 2020
Chinese Calendars: Year 2021 to 2030
Chinese Calendars: Year 2031 to 2040
Chinese Calendars: Year 2041 to 2050
Chinese Calendars: Year 2051 to 2060
Chinese Calendars: Year 2061 to 2070
Chinese Calendars: Year 2071 to 2080
Chinese Calendars: Year 2081 to 2090