datecode,interpretation,edate,ldate
0, "Undated", 0, 0                                                              
100, "Prehistoric pre AD 43)", -100000, 43                                      
110, "Palaeolithic >10,000 BC)", -500000, -10000                                
111, "Early Palaeolithic", -500000, -150000                                     
112, "Middle Palaeolithic", -150000, -40000                                     
113, "Upper Palaeolithic", -40000, -10000                                       
120, "Mesolithic 10,000-3,500 BC)", -10000, -4000                               
121, "Early Mesolithic", -10000, -7000                                          
122, "Late Mesolithic", -7000, -4000                                            
130, "Neolithic 4,000-2,200 BC)", -4000, -2200                                  
131, "Early Neolithic", -4000, -3000                                            
132, "Middle Neolithic", -3500, -2700                                           
133, "Late Neolithic", -3000, -2200                                             
140, "Bronze Age 2,000-600 BC)", -2000, -600                                    
141, "Early Bronze Age", -2500, -1500                                           
142, "Middle Bronze Age", -1600, -1000                                          
143, "Late Bronze Age", -1000, -700                                             
150, "Iron Age 800 BC -AD 43)", -800, 43                                        
151, "Early Iron Age", -800, -400                                               
152, "Middle Iron Age", -400, -100                                              
153, "Late Iron Age", -100, 43                                                  
200, "Roman AD 43 - c AD 410)", 43, 410                                         
201, "1st century", 0, 100                                                      
202, "2nd century", 100, 200                                                    
203, "3rd century", 200, 300                                                    
204, "4th century", 300, 400                                                    
300, "Anglian c AD 410 - AD 864)", 410, 864                                     
305, "5th century", 400, 500                                                    
306, "6th century", 500, 600                                                    
307, "7th century", 600, 700                                                    
308, "8th century", 700, 800                                                    
309, "9th century", 800, 864                                                    
309.41, "841", 841, 841                                                         
309.43, "843", 843, 843                                                         
400, "Anglo-Scandinavian c AD 864 - 1066)", 864, 1066                           
409, "9th century", 864, 900                                                    
410, "10th century", 900, 1000                                                  
411, "11th century", 1000, 1066                                                 
500, "Medieval AD 1066 - AD 1540)", 1066, 1540                                  
511, "11th century", 1066, 1100                                                 
512, "12th century", 1100, 1200                                                 
513, "13th century", 1200, 1300                                                 
514, "14th century", 1300, 1400                                                 
515, "15th century", 1400, 1500                                                 
516, "16th century", 1500, 1600                                                 
600, "Post-Medieval AD 1540 - 1901)", 1540, 1901                                
617, "17th century", 1600, 1700                                                 
618, "18th century", 1700, 1800                                                 
619, "19th century", 1800, 1900                                                 
620, "20th century", 1900, 2000