He did not pay zakaah due to ignorance, and now his money has decreased
Question

                I live in my own home, and my salary is not enough for me. But by Allah’s grace, I learnt welding, and He blessed me with extra money from this plus my normal salary. I have gathered about 9 million dinar, and more than a full year passed on this amount. When I asked about Zakat, some brothers who are not knowledgeable said to me that I am not obliged to pay Zakat as the home I live in is incomplete and it needs more money to complete it. Then Allah decreed that I stop working due to the sectarian violence in Iraq. So I spent from the money I gathered earlier. Few months passed and now I have 5 million Iraqi dinar.

My question is: 

Do I have to pay Zakat on the remaining amount of money? If yes then how much should I pay out of my money?.
Praise be to Allah.
    If a person owns the nisaab (minimum threshold) and a year 
    has passed, then he must pay zakaah, even if the wealth is prepared for 
    Hajj, getting married, building a house or anything else. 

    The nisaab is the equivalent of 85 grams of gold or 595 grams 
    of silver. 

    Based on this, when one year had passed you should have paid 
    zakaah on the wealth that you had, and you were wrong to follow the opinions 
    of your friends, and they were wrong to issue fatwas without knowledge. 

    The zakaah that you did not pay is still a debt that you owe, 
    and you have to pay it now, and repent to Allaah for delaying it. 

    The amount that you have to pay is one quarter of one tenth 
    (2.5%), i.e., 25 in every thousand. 

    So the zakaah on 9 million is 225,000, two hundred and twenty 
    five thousand dinars. 

    When the new year ends, look at the money that you have left, 
    and if it reaches the nisaab then you have to pay zakaah on it. 

    Shaykh Ibn Baaz (may Allaah have mercy on him) was asked 
    about not paying zakaah for five years out of ignorance.  

    He replied: You have to pay zakaah for all the past years, 
    and it is not waived due to your ignorance, because the obligation of zakaah 
    is something that no Muslim has any excuse for not knowing, and the ruling 
    is well known to all Muslims. Zakaah is the third pillar of Islam. What you 
    must do is hasten to pay zakaah for all the past years, and repent to 
    Allaah, may He be glorified and exalted, for delaying it. May Allaah forgive 
    us and you and all the Muslims. And Allaah is the Source of strength. 

    End quote from Majmoo’ Fataawa al-Shaykh Ibn Baaz 
    (14/239). 

    To sum up: You have to pay zakaah on the past years, and you 
    have to pay it because it is something that is still required of you, and 
    the fact that the money has decreased now does not count. 

    For information on those to whom zakaah may be given, please 
    see the answer to question no. 
    46209. 

    And Allaah knows best.