Ngokwe-International Service for Earth Rotation and Reference Systems (IERS), kwaye ayisiyonto yokuhlekisa, yile nto kuthiwa liziko, Isibini esongeziweyo kuya kufuneka songezwe kuDisemba 31, 2016 ukuze sikwazi ukulungelelanisa ixesha elichanekileyo ngokuchanekileyo. Siza kuthetha kancinci ngale yesibini yesibini eyongezelelweyo ekuya kufuneka siyongeze kunyaka wethu ka-2016 ukuba sifuna yonke into iqhubeke ukuhamba kakuhle ngokwexesha, okwangoku, siza kuwela iminwe yethu ukuze kungabikho nalinye lomculo ngendlela, kwaye unyaka ka-2016 umnyama ngakumbi kubo.
Olu longezo lwesibini, njengoko besixelela Gizmodo, yaziwa njenge «xhuma okwesibini»Kwaye yindlela esetyenziselwa ukubuyisa utshintsho kumjikelo woMhlaba oguqula iwotshi. Njengoko besitsho, kwiminyaka engama-200 eyadlulayo, usuku lwelanga lwathatha imizuzwana engama-86.400; kule mihla ihlala malunga nemizuzwana engama-86.400,002, kwaye kubonakala ngathi isantya sokujikeleza komhlaba siyancipha ngendlela engenamsebenzi kodwa eqondakalayo (imizuzwana emibini qho emva kweminyaka engamakhulu amabini ayimibi kwaphela). Iiwotshi kufuneka emva koko yongeza umahluko ukuqhubeka nokusebenza ngokufanelekileyo.
Ngamanye amaxesha, njengalo nyaka ka-2016, kunyanzelekile ukuba ungeze okanye uthabathe owesibini, into esele yenziwe ukusukela nge1972 kwaye ngoku eqinisekisa ukusebenza ngokukuko kwenkqubo yethu yexesha. Ngokwesiqhelo, lo wesibini ngaphezulu okanye ngaphantsi wongezwa phakathi kwenyanga kaJuni okanye uDisembaNgeli xesha kongezwe nge-31 kaDisemba, zilumkele izihlobo, uya kuba nesibini esinye isonka sokutya iidiliya. Okwesibini kunokubangela iimpazamo ezinkulu zekhompyuter, yiyo loo nto kukho iingcali ezilindele olu hlobo lokwahluka okungabonakaliyo. Ngamafutshane, u-2016 uyahamba kwaye sinethemba lokuba ngo-2017 uza kuqhubeka usithemba.